diff --git a/src/Makefile b/src/Makefile
index a9b706f44..eb74178cb 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -462,6 +462,7 @@ DBGNAME?=$(EXENAME).debug
 OBJS:=$(i_main_o) \
 		$(OBJDIR)/comptime.o \
 		$(OBJDIR)/string.o   \
+		$(OBJDIR)/d_async.o  \
 		$(OBJDIR)/d_main.o   \
 		$(OBJDIR)/d_protocol.o   \
 		$(OBJDIR)/d_clisrv.o \
diff --git a/src/command.c b/src/command.c
index 165cbb584..ad4afb2b7 100644
--- a/src/command.c
+++ b/src/command.c
@@ -18,6 +18,7 @@
 
 #include "doomdef.h"
 #include "doomstat.h"
+#include "d_main.h"
 #include "command.h"
 #include "console.h"
 #include "z_zone.h"
@@ -34,6 +35,8 @@
 #include "p_setup.h"
 #include "lua_script.h"
 #include "d_netfil.h" // findfile
+#include "d_async.h"
+#include "filesrch.h"
 
 //========
 // protos.
@@ -121,11 +124,9 @@ void COM_BufAddText(const char *ptext)
 	l = strlen(ptext);
 
 	if (com_text.cursize + l >= com_text.maxsize)
-	{
 		CONS_Alert(CONS_WARNING, M_GetText("Command buffer full!\n"));
-		return;
-	}
-	VS_Write(&com_text, ptext, l);
+	else
+		VS_Write(&com_text, ptext, l);
 }
 
 /** Adds command text and executes it immediately.
@@ -752,12 +753,60 @@ static void COM_CEchoDuration_f(void)
 		HU_SetCEchoDuration(atoi(COM_Argv(1)));
 }
 
+struct COM_Exec_Ctx
+{
+	boolean   noerror;
+	boolean   silent;
+	UINT8   * buf;
+};
+
+static void Free_COM_Exec_Ctx (struct COM_Exec_Ctx *ctx)
+{
+	Z_Free(ctx->buf);
+	Z_Free(ctx);
+}
+
+void COM_ExecuteFile (void *p, void *u)
+{
+	filequery_t         * q   = p;
+	struct COM_Exec_Ctx * ctx = u;
+
+	ctx->buf = NULL;
+
+	if (q->status == FS_FOUND)
+	{
+		FIL_ReadFile(q->filename, &ctx->buf);
+	}
+
+	if (ctx->buf)
+	{
+		if (! ctx->silent)
+			CONS_Printf(M_GetText("executing %s\n"), q->filename);
+
+		// insert text file into the command buffer
+		COM_BufAddText((char *)ctx->buf);
+		COM_BufAddText("\n");
+	}
+	else
+	{
+		if (! ctx->noerror)
+			CONS_Printf(M_GetText("couldn't execute file %s\n"), q->filename);
+	}
+
+	Free_COM_Exec_Ctx(ctx);
+}
+
 /** Executes a script file.
   */
 static void COM_Exec_f(void)
 {
-	UINT8 *buf = NULL;
-	char filename[256];
+	char filenamebuf[MAX_WADPATH];
+
+	struct COM_Exec_Ctx *ctx;
+
+	const char * filename;
+
+	filequery_t q;
 
 	if (COM_Argc() < 2 || COM_Argc() > 3)
 	{
@@ -765,37 +814,39 @@ static void COM_Exec_f(void)
 		return;
 	}
 
-	// load file
-	// Try with Argv passed verbatim first, for back compat
-	FIL_ReadFile(COM_Argv(1), &buf);
+	filename = COM_Argv(1);
 
-	if (!buf)
+	ctx = ZZ_Alloc(sizeof *ctx);
+
+	ctx->noerror  = COM_CheckParm("-noerror");
+	ctx->silent   = COM_CheckParm("-silent");
+
+	if (COM_CheckParm("-sync"))
 	{
-		// Now try by searching the file path
-		// filename is modified with the full found path
-		strcpy(filename, COM_Argv(1));
-		if (findfile(filename, NULL, true) != FS_NOTFOUND)
-			FIL_ReadFile(filename, &buf);
+		q.filename = filenamebuf;
 
-		if (!buf)
+		strcpy(q.filename, filename);
+
+		if (FIL_FileOK(filename))
 		{
-			if (!COM_CheckParm("-noerror"))
-				CONS_Printf(M_GetText("couldn't execute file %s\n"), COM_Argv(1));
-			return;
+			q.status = FS_FOUND;
 		}
+		else
+		{
+			q.status = findfile(q.filename, NULL, true);
+		}
+
+		COM_ExecuteFile(&q, ctx);
+	}
+	else
+	{
+		q.filename = strcpy(ZZ_Alloc(MAX_WADPATH), filename);
+		Append_async_addfile(ASYNC_EXEC, q.filename, ctx);
 	}
 
-	if (!COM_CheckParm("-silent"))
-		CONS_Printf(M_GetText("executing %s\n"), COM_Argv(1));
-
-	// insert text file into the command buffer
-	COM_BufAddText((char *)buf);
-	COM_BufAddText("\n");
-
-	// free buffer
-	Z_Free(buf);
 }
 
+
 /** Delays execution of the rest of the commands until the next frame.
   * Allows sequences of commands like "jump; fire; backward".
   */
diff --git a/src/command.h b/src/command.h
index 2276a0ae2..5a32d0241 100644
--- a/src/command.h
+++ b/src/command.h
@@ -59,6 +59,9 @@ void COM_ImmedExecute(const char *ptext);
 // Execute commands in buffer, flush them
 void COM_BufExecute(void);
 
+// Execute a whole file (internal use only :v)
+void COM_ExecuteFile(void *query, void *ctx);
+
 // As above; and progress the wait timer.
 void COM_BufTicker(void);
 
diff --git a/src/console.c b/src/console.c
index 73eac9ff9..3e22c295d 100644
--- a/src/console.c
+++ b/src/console.c
@@ -1414,6 +1414,14 @@ void CONS_Printf(const char *fmt, ...)
 	startup = con_startup;
 
 	Unlock_state();
+	
+
+#ifdef HAVE_THREADS
+	if (! I_on_main_thread())
+	{
+		return;
+	}
+#endif
 
 	// if not in display loop, force screen update
 	if (startup)
diff --git a/src/d_async.c b/src/d_async.c
new file mode 100644
index 000000000..67483b917
--- /dev/null
+++ b/src/d_async.c
@@ -0,0 +1,259 @@
+// SONIC ROBO BLAST 2 KART
+//-----------------------------------------------------------------------------
+// Copyright (C) 2020 by James R.
+//
+// This program is free software distributed under the
+// terms of the GNU General Public License, version 2.
+// See the 'LICENSE' file for more details.
+//-----------------------------------------------------------------------------
+/// \file  d_async.c
+/// \brief Add wad/exec config asynchronously to the main thread, but in order
+
+#include "doomdef.h"
+#include "d_main.h"
+#include "d_async.h"
+#include "filesrch.h"
+#include "i_threads.h"
+#include "m_misc.h"
+#include "p_setup.h"
+#include "z_zone.h"
+
+struct filename_queue;
+struct async_addfile;
+
+typedef struct filename_queue filename_queue_t;
+typedef struct async_addfile async_addfile_t;
+
+struct filename_queue
+{
+	int                type;
+	char             * name;
+	void             * u;/* exec command has some parameters that need know */
+	filename_queue_t * next;
+};
+
+struct async_addfile
+{
+	int               done;
+	int               query_size;
+	int               query_position;
+	filequery_t     * query;
+	int             * type;
+	void           ** u;
+	async_addfile_t * next;
+};
+
+static filename_queue_t * queue_head;
+static filename_queue_t * queue_tail;
+static int                queue_size;
+
+static I_mutex            async_mutex;
+
+static async_addfile_t  * async_head;
+static async_addfile_t  * async_tail;
+
+static void
+Async_addfile_thread (async_addfile_t *file)
+{
+	findmultiplefiles(file->query_size, file->query, false, true, &async_mutex);
+
+	I_lock_mutex(&async_mutex);
+	{
+		file->done = 1;
+	}
+	I_unlock_mutex(async_mutex);
+}
+
+static void
+Do_addfile (int type, filequery_t *q, void *ctx)
+{
+	switch (type)
+	{
+		case ASYNC_EXEC:
+			COM_ExecuteFile(q, ctx);
+			break;
+	}
+}
+
+void
+Finish_async_addfile (void)
+{
+	async_addfile_t * file = async_head;
+	async_addfile_t * next;
+
+	filequery_t * q;
+
+	filestatus_t status;
+
+	int type;
+	int done;
+
+	while (file != NULL)
+	{
+		while (file->query_position < file->query_size)
+		{
+			q    = &file->query [file->query_position];
+			type =  file->type  [file->query_position];
+
+			I_lock_mutex(&async_mutex);
+			{
+				status = q->status;
+			}
+			I_unlock_mutex(async_mutex);
+
+			if (status == FS_NOTCHECKED)
+			{
+				break;
+			}
+			else
+			{
+				Do_addfile(type, q, file->u[file->query_position]);
+			}
+
+			Z_Free(q->filename);
+
+			file->query_position++;
+		}
+
+		if (file->query_position < file->query_size)
+		{
+			break;
+		}
+
+		I_lock_mutex(&async_mutex);
+		{
+			done = file->done;
+		}
+		I_unlock_mutex(async_mutex);
+
+		if (done)
+		{
+			next = file->next;
+
+			Z_Free(file->u);
+			Z_Free(file->type);
+			Z_Free(file->query);
+			Z_Free(file);
+
+			file = next;
+		}
+		else
+		{
+			break;
+		}
+	}
+
+	async_head = file;
+
+	if (file == NULL)
+	{
+		async_tail = NULL;
+	}
+}
+
+void
+Append_async_addfile (int type, const char * filename, void * userdata)
+{
+	char filenamebuf[MAX_WADPATH];
+
+	filename_queue_t * q;
+
+	filequery_t file;
+
+	if (FIL_FileOK(filename))
+	{
+		file.status   = FS_FOUND;
+		file.filename = filenamebuf;
+
+		strcpy(file.filename, filename);
+
+		Do_addfile(type, &file, userdata);
+	}
+	else
+	{
+		q = ZZ_Alloc(sizeof *q);
+
+		if (queue_tail != NULL)
+		{
+			queue_tail->next = q;
+		}
+		else
+		{
+			queue_head = q;
+		}
+
+		queue_tail = q;
+		queue_size++;
+
+		q->type = type;
+		q->name = strcpy(ZZ_Alloc(MAX_WADPATH), filename);
+		q->u    = userdata;
+		q->next = NULL;
+	}
+}
+
+void
+Detach_async_addfile (void)
+{
+	filename_queue_t * q = queue_head;
+	filename_queue_t * next;
+
+	async_addfile_t  * file;
+
+	filequery_t      * query;
+	int              * type;
+	void            ** udata;
+
+	if (q != NULL)
+	{
+		file = ZZ_Alloc(sizeof *file);
+
+		if (async_tail != NULL)
+		{
+			async_tail->next = file;
+		}
+		else
+		{
+			async_head = file;
+		}
+
+		async_tail = file;
+
+		file->done = 0;
+		file->next = NULL;
+
+		file->query_size     = queue_size;
+		file->query_position = 0;
+
+		file->query = ZZ_Alloc(queue_size * sizeof (*file->query));
+		file->type  = ZZ_Alloc(queue_size * sizeof (*file->type));
+		file->u     = ZZ_Alloc(queue_size * sizeof (*file->u));
+
+		query = file->query;
+		type  = file->type;
+		udata = file->u;
+
+		do
+		{
+			*type++  = q->type;
+			*udata++ = q->u;
+
+			query->status       = FS_NOTCHECKED;
+			query->wantedmd5sum = NULL;
+			query->filename     = q->name;
+			query++;
+
+			next = q->next;
+
+			Z_Free(q);
+		}
+		while (( q = next ) != NULL) ;
+
+		I_spawn_thread("async-addfile",
+				(I_thread_fn)Async_addfile_thread, file);
+
+		queue_head = NULL;
+		queue_tail = NULL;
+		queue_size = 0;
+	}
+}
diff --git a/src/d_async.h b/src/d_async.h
new file mode 100644
index 000000000..9c2b7e34e
--- /dev/null
+++ b/src/d_async.h
@@ -0,0 +1,44 @@
+// SONIC ROBO BLAST 2 KART
+//-----------------------------------------------------------------------------
+// Copyright (C) 2020 by James R.
+//
+// This program is free software distributed under the
+// terms of the GNU General Public License, version 2.
+// See the 'LICENSE' file for more details.
+//-----------------------------------------------------------------------------
+/// \file  d_async.h
+/// \brief Add wad/exec config asynchronously to the main thread, but in order
+
+#ifndef D_ASYNC_H
+#define D_ASYNC_H
+
+enum
+{
+	ASYNC_ADDFILE,
+	ASYNC_EXEC,
+};
+
+/*
+Queue a file to be added. Detach_async_addfile will spawn a thread that
+searches for any files if necessary.
+*/
+
+void Append_async_addfile (int type, const char * filename, void * ctx);
+
+/*
+Although the file searching is done on another thread, the actual adding of the
+wad or executing the config must be done on the main thread. This function is
+called every tic to check if a file was found so it can perform that last step.
+It does this in order.
+*/
+
+void Finish_async_addfile (void);
+
+/*
+Spawns a thread that searches for files that were queued.
+Called at the end of each tic.
+*/
+
+void Detach_async_addfile (void);
+
+#endif/*D_ASYNC_H*/
diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index 1749d9aea..3d4e3b674 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -45,6 +45,7 @@
 #include "lua_script.h"
 #include "lua_hook.h"
 #include "k_kart.h"
+#include "d_async.h"
 #include "s_sound.h" // sfx_syfail
 #include "m_perfstats.h"
 #include "d_main.h"
@@ -6041,6 +6042,8 @@ boolean TryRunTics(tic_t realtics)
 
 	if (singletics)
 		realtics = 1;
+	
+	Finish_async_addfile();
 
 	if (realtics >= 1)
 	{
@@ -6118,6 +6121,8 @@ boolean TryRunTics(tic_t realtics)
 	{
 		hu_stopped = true;
 	}
+	
+	Detach_async_addfile();
 
 	return ticking;
 }
diff --git a/src/d_netfil.c b/src/d_netfil.c
index a51d44f80..436926269 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -1164,13 +1164,13 @@ filestatus_t checkfilemd5(char *filename, const UINT8 *wantedmd5sum)
 // Rewritten by Monster Iestyn to be less stupid
 // Note: if completepath is true, "filename" is modified, but only if FS_FOUND is going to be returned
 // (Don't worry about WinCE's version of filesearch, nobody cares about that OS anymore)
-filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean completepath)
+filestatus_t findmultiplefiles(int n, filequery_t *files, boolean checkmd5, boolean completepath, void *mutex_ptr)
 {
 	filestatus_t homecheck; // store result of last file search
 	boolean badmd5 = false; // store whether md5 was bad from either of the first two searches (if nothing was found in the third)
 
 	// first, check SRB2's "home" directory
-	homecheck = filesearch(filename, srb2home, wantedmd5sum, completepath, 10);
+	homecheck = filesearch(n, files, srb2home, checkmd5, completepath, 10, mutex_ptr);
 
 	if (homecheck == FS_FOUND) // we found the file, so return that we have :)
 		return FS_FOUND;
@@ -1179,7 +1179,7 @@ filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean complet
 	// if not found at all, just move on without doing anything
 
 	// next, check SRB2's "path" directory
-	homecheck = filesearch(filename, srb2path, wantedmd5sum, completepath, 10);
+	homecheck = filesearch(n, files, srb2path, checkmd5, completepath, 10, mutex_ptr);
 
 	if (homecheck == FS_FOUND) // we found the file, so return that we have :)
 		return FS_FOUND;
@@ -1188,7 +1188,7 @@ filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean complet
 	// if not found at all, just move on without doing anything
 
 	// finally check "." directory
-	homecheck = filesearch(filename, ".", wantedmd5sum, completepath, 10);
+	homecheck = filesearch(n, files, ".", checkmd5, completepath, 10, mutex_ptr);
 
 	if (homecheck != FS_NOTFOUND) // if not found this time, fall back on the below return statement
 		return homecheck; // otherwise return the result we got
@@ -1196,6 +1196,12 @@ filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean complet
 	return (badmd5 ? FS_MD5SUMBAD : FS_NOTFOUND); // md5 sum bad or file not found
 }
 
+filestatus_t findfile(char *filename, const UINT8 *wantedmd5sum, boolean completepath)
+{
+	filequery_t q = { FS_NOTFOUND, wantedmd5sum, filename };
+	return findmultiplefiles(1, &q, ( wantedmd5sum != NULL ), completepath, NULL);
+}
+
 #ifdef HAVE_CURL
 size_t curlwrite_data(void *ptr, size_t size, size_t nmemb, FILE *stream)
 {
diff --git a/src/filesrch.c b/src/filesrch.c
index e2acdf324..09b238376 100644
--- a/src/filesrch.c
+++ b/src/filesrch.c
@@ -29,6 +29,7 @@
 #include "m_misc.h"
 #include "z_zone.h"
 #include "m_menu.h" // Addons_option_Onchange
+#include "i_threads.h"
 
 #if defined (_WIN32) && defined (_MSC_VER)
 
@@ -354,17 +355,44 @@ INT32 pathisdirectory(const char *path)
 	return 0;
 }
 
-filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *wantedmd5sum, boolean completepath, int maxsearchdepth)
+filestatus_t filesearch(int nfiles, filequery_t *files, const char *startpath, boolean checkmd5, boolean completepath, int maxsearchdepth, void *mutex_ptr)
 {
 	filestatus_t retval = FS_NOTFOUND;
+	const UINT8 *wantedmd5sum = NULL;
 	DIR **dirhandle;
 	struct dirent *dent;
 	struct stat fsstat;
-	int found = 0;
-	char *searchname = strdup(filename);
 	int depthleft = maxsearchdepth;
 	char searchpath[1024];
 	size_t *searchpathindex;
+	int matched;
+	int files_left = 0;
+	int i;
+
+#ifdef HAVE_THREADS
+#define   Lock() I_lock_mutex    ((I_mutex *)mutex_ptr)
+#define Unlock() I_unlock_mutex (((mutex_ptr) ? *(I_mutex *)mutex_ptr : NULL))
+#else
+#define   Lock() ((void)0)
+#define Unlock() ((void)0)
+#endif
+
+	Lock();
+
+	for (i = 0; i < nfiles; ++i)
+	{
+		if (files[i].status != FS_FOUND)
+		{
+			files_left++;
+		}
+	}
+
+	Unlock();
+
+	if (! files_left)
+	{
+		return FS_FOUND;
+	}
 
 	dirhandle = (DIR**) malloc(maxsearchdepth * sizeof (DIR*));
 	searchpathindex = (size_t *) malloc(maxsearchdepth * sizeof (size_t));
@@ -376,7 +404,6 @@ filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *want
 
 	if (dirhandle[depthleft] == NULL)
 	{
-		free(searchname);
 		free(dirhandle);
 		free(searchpathindex);
 		return FS_NOTFOUND;
@@ -390,7 +417,7 @@ filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *want
 	else
 		searchpathindex[depthleft]--;
 
-	while ((!found) && (depthleft < maxsearchdepth))
+	while ((files_left) && (depthleft < maxsearchdepth))
 	{
 		searchpath[searchpathindex[depthleft]]=0;
 		dent = readdir(dirhandle[depthleft]);
@@ -448,34 +475,75 @@ filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *want
 			searchpath[searchpathindex[depthleft]-1]='/';
 			searchpath[searchpathindex[depthleft]]=0;
 		}
-		else if (!strcasecmp(searchname, dent->d_name))
+		else
 		{
-			switch (checkfilemd5(searchpath, wantedmd5sum))
+			for (i = 0; i < nfiles; ++i)
 			{
-				case FS_FOUND:
-					if (completepath)
-						strcpy(filename,searchpath);
-					else
-						strcpy(filename,dent->d_name);
-					retval = FS_FOUND;
-					found = 1;
-					break;
-				case FS_MD5SUMBAD:
-					retval = FS_MD5SUMBAD;
-					break;
-				default: // prevent some compiler warnings
-					break;
+				Lock();
+
+				if (checkmd5)
+				{
+					wantedmd5sum = files[i].wantedmd5sum;
+				}
+
+				matched =  (
+						files[i].status != FS_FOUND &&
+						!strcasecmp(files[i].filename, dent->d_name)
+				);
+
+				Unlock();
+
+				if (matched)
+				{
+					switch (checkfilemd5(searchpath, wantedmd5sum))
+					{
+						case FS_FOUND:
+							Lock();
+
+							if (completepath)
+								strcpy(files[i].filename,searchpath);
+							else
+								strcpy(files[i].filename,dent->d_name);
+							files[i].status = FS_FOUND;
+
+							Unlock();
+
+							files_left--;
+							break;
+						case FS_MD5SUMBAD:
+							Lock();
+							retval = files[i].status = FS_MD5SUMBAD;
+							Unlock();
+							break;
+						default: // prevent some compiler warnings
+							break;
+					}
+				}
 			}
 		}
 	}
 
 	for (; depthleft < maxsearchdepth; closedir(dirhandle[depthleft++]));
 
-	free(searchname);
 	free(searchpathindex);
 	free(dirhandle);
 
-	return retval;
+	Lock();
+	{
+		for (i = 0; i < nfiles; ++i)
+		{
+			if (files[i].status != FS_FOUND && files[i].status != FS_MD5SUMBAD)
+			{
+				files[i].status = FS_NOTFOUND;
+			}
+		}
+	}
+	Unlock();
+
+	return ( (files_left) ? retval : FS_FOUND );
+
+#undef   Lock
+#undef Unlock
 }
 
 char exttable[NUM_EXT_TABLE][7] = { // maximum extension length (currently 4) plus 3 (null terminator, stop, and length including previous two)
diff --git a/src/filesrch.h b/src/filesrch.h
index b991e8b16..6d10561ae 100644
--- a/src/filesrch.h
+++ b/src/filesrch.h
@@ -8,25 +8,38 @@
 #include "d_netfil.h"
 #include "m_menu.h" // MAXSTRINGLENGTH
 
+typedef struct
+{
+	filestatus_t   status;
+	const UINT8  * wantedmd5sum;
+	char         * filename;
+}
+filequery_t;
+
 extern consvar_t cv_addons_option, cv_addons_folder, cv_addons_md5, cv_addons_showall, cv_addons_search_case, cv_addons_search_type;
 
 /**	\brief	The filesearch function
 
 	This function search files, manly WADs and return back the status of the file
 
-	\param	filename	the file to look for
+	\param	nfiles		number of files
+	\param	queries		the files to look for
 	\param	startpath	where to start look from
-	\param	wantedmd5sum	want to check with MD5
 	\param	completepath	want to return the complete path of the file?
 	\param	maxsearchdepth	the max depth to search for the file
 
-	\return	filestatus_t
+	\return	FS_FOUND if all files were found, FS_NOTFOUND or FS_MD5SUMBAD
+		if some files were not found
 
 
 */
 
-filestatus_t filesearch(char *filename, const char *startpath, const UINT8 *wantedmd5sum,
-	boolean completepath, int maxsearchdepth);
+filestatus_t filesearch(int nfiles, filequery_t *queries, const char *startpath,
+	boolean checkmd5, boolean completepath, int maxsearchdepth, void *mutex_ptr);
+
+/* this is a better place for it tbh (im still too lazy to move the other) */
+filestatus_t findmultiplefiles(int nfiles, filequery_t *files,
+		boolean checkmd5, boolean completepath, void *mutex_ptr);
 
 #define menudepth 20
 
diff --git a/src/i_threads.h b/src/i_threads.h
index 45a3dcc3e..2e02713a9 100644
--- a/src/i_threads.h
+++ b/src/i_threads.h
@@ -27,6 +27,8 @@ void      I_spawn_thread (const char *name, I_thread_fn, void *userdata);
 /* check in your thread whether to return early */
 int       I_thread_is_stopped (void);
 
+int       I_on_main_thread  (void);
+
 void      I_lock_mutex      (I_mutex *);
 void      I_unlock_mutex    (I_mutex);
 
diff --git a/src/m_misc.c b/src/m_misc.c
index a8cc28f0b..015972672 100644
--- a/src/m_misc.c
+++ b/src/m_misc.c
@@ -504,7 +504,7 @@ void M_FirstLoadConfig(void)
 	CV_InitFilterVar();
 
 	// load config, make sure those commands doesnt require the screen...
-	COM_BufInsertText(va("exec \"%s\"\n", configfile));
+	COM_BufInsertText(va("exec \"%s\" -sync\n", configfile));
 	// no COM_BufExecute() needed; that does it right away
 
 	// don't filter anymore vars and don't let this convsvar be changed
diff --git a/src/sdl/i_system.c b/src/sdl/i_system.c
index 0e921d73b..faa7d1ab0 100644
--- a/src/sdl/i_system.c
+++ b/src/sdl/i_system.c
@@ -3871,10 +3871,14 @@ static void pathonly(char *s)
 static const char *searchWad(const char *searchDir)
 {
 	static char tempsw[256] = "";
+	filequery_t fsquery;
 	filestatus_t fstemp;
+	
+	fsquery.filename = tempsw;
 
 	strcpy(tempsw, WADKEYWORD1);
-	fstemp = filesearch(tempsw,searchDir,NULL,true,20);
+	fsquery.status = FS_NOTFOUND;
+	fstemp = filesearch(1,&fsquery,searchDir,false,true,20,NULL);
 	if (fstemp == FS_FOUND)
 	{
 		pathonly(tempsw);
@@ -3882,7 +3886,7 @@ static const char *searchWad(const char *searchDir)
 	}
 
 	strcpy(tempsw, WADKEYWORD2);
-	fstemp = filesearch(tempsw, searchDir, NULL, true, 20);
+	fstemp = filesearch(1, &fsquery, searchDir, false, true, 20, NULL);
 	if (fstemp == FS_FOUND)
 	{
 		pathonly(tempsw);
diff --git a/src/sdl/i_threads.c b/src/sdl/i_threads.c
index 078f4e0f4..f2bd82c01 100644
--- a/src/sdl/i_threads.c
+++ b/src/sdl/i_threads.c
@@ -47,6 +47,8 @@ static I_mutex        i_cond_pool_mutex;
 
 static SDL_atomic_t   i_threads_running = {1};
 
+static SDL_threadID   i_main_thread_id;
+
 static Link
 Insert_link (
 		Link * head,
@@ -197,6 +199,12 @@ I_thread_is_stopped (void)
 	return ( ! SDL_AtomicGet(&i_threads_running) );
 }
 
+int
+I_on_main_thread (void)
+{
+	return ( SDL_ThreadID() == i_main_thread_id );
+}
+
 void
 I_start_threads (void)
 {
@@ -211,6 +219,8 @@ I_start_threads (void)
 	)){
 		abort();
 	}
+	
+	i_main_thread_id = SDL_ThreadID();
 }
 
 void
@@ -283,6 +293,12 @@ I_lock_mutex (
 		I_mutex * anchor
 ){
 	SDL_mutex * mutex;
+	
+	if (! i_threads_running.value)
+		return;
+
+	if (anchor == NULL)
+		return;
 
 	mutex = Identity(
 			&i_mutex_pool,
@@ -299,6 +315,12 @@ void
 I_unlock_mutex (
 		I_mutex id
 ){
+	if (! i_threads_running.value)
+		return;
+
+	if (id == NULL)
+		return;
+	
 	if (SDL_UnlockMutex(id) == -1)
 		abort();
 }
@@ -309,6 +331,12 @@ I_hold_cond (
 		I_mutex   mutex_id
 ){
 	SDL_cond * cond;
+	
+	if (! i_threads_running.value)
+		return;
+
+	if (cond_anchor == NULL || mutex_id == NULL)
+		return;
 
 	cond = Identity(
 			&i_cond_pool,
@@ -326,6 +354,12 @@ I_wake_one_cond (
 		I_cond * anchor
 ){
 	SDL_cond * cond;
+	
+	if (! i_threads_running.value)
+		return;
+
+	if (anchor == NULL)
+		return;
 
 	cond = Identity(
 			&i_cond_pool,
@@ -343,6 +377,12 @@ I_wake_all_cond (
 		I_cond * anchor
 ){
 	SDL_cond * cond;
+	
+	if (! i_threads_running.value)
+		return;
+
+	if (anchor == NULL)
+		return;
 
 	cond = Identity(
 			&i_cond_pool,
diff --git a/src/w_wad.c b/src/w_wad.c
index 44bb71ee9..ebc6c25cb 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -904,17 +904,46 @@ void W_UnloadWadFile(UINT16 num)
   */
 INT32 W_InitMultipleFiles(char **filenames, boolean addons)
 {
+	char filenamebufs[MAX_WADFILES][MAX_WADPATH];
+	filequery_t q[MAX_WADFILES];
+
+	int n = 0;
+	int i;
+	
 	INT32 rc = 1;
 	INT32 overallrc = 1;
 
 	// will be realloced as lumps are added
 	for (; *filenames; filenames++)
 	{
-		if (addons && !W_VerifyNMUSlumps(*filenames))
+		if (FIL_FileOK(*filenames))
+		{
+			q[n].status   = FS_FOUND;
+			q[n].filename = *filenames;
+		}
+		else
+		{
+			strcpy(filenamebufs[n], *filenames);
+			q[n].filename = filenamebufs[n];
+		}
+		n++;
+	}
+
+	findmultiplefiles(n, q, false, true, NULL);
+
+	for (i = 0; i < n; ++i)
+	{
+		if (q[i].status != FS_FOUND)
+		{
+			CONS_Alert(CONS_ERROR, M_GetText("File %s not found.\n"), q[i].filename);
+			continue;
+		}
+
+		if (addons && !W_VerifyNMUSlumps(q[i].filename))
 			G_SetGameModified(true, false);
 
 		//CONS_Debug(DBG_SETUP, "Loading %s\n", *filenames);
-		rc = W_InitFile(*filenames, 0, 0, false);
+		rc = W_InitFile(q[i].filename, 0, 0, false);
 		if (rc == INT16_MAX)
 			CONS_Printf(M_GetText("Errors occurred while loading %s; not added.\n"), *filenames);
 		overallrc &= (rc != INT16_MAX) ? 1 : 0;
diff --git a/src/z_zone.c b/src/z_zone.c
index b0223460b..c049e5e20 100644
--- a/src/z_zone.c
+++ b/src/z_zone.c
@@ -29,6 +29,7 @@
 #include "doomstat.h"
 #include "r_patch.h"
 #include "i_system.h" // I_GetFreeMem
+#include "i_threads.h"
 #include "i_video.h" // rendermode
 #include "z_zone.h"
 #include "m_misc.h" // M_Memcpy
@@ -50,6 +51,16 @@ static boolean Z_calloc = false;
 //#define ZDEBUG2
 #endif
 
+#ifdef HAVE_THREADS
+static I_mutex z_mutex;
+
+#  define Lock_state()    I_lock_mutex(&z_mutex)
+#  define Unlock_state() I_unlock_mutex(z_mutex)
+#else/*HAVE_THREADS*/
+#  define Lock_state()
+#  define Unlock_state()
+#endif/*HAVE_THREADS*/
+
 typedef struct memblock_s
 {
 	void **user;
@@ -135,6 +146,8 @@ void Z_Free(void *ptr)
 	CONS_Debug(DBG_MEMORY, "Z_Free %s:%d\n", file, line);
 #endif
 
+	Lock_state();
+
 	block = MEMBLOCK(ptr);
 #ifdef PARANOIA
 	if (block->id != ZONEID)
@@ -167,6 +180,8 @@ void Z_Free(void *ptr)
 	block->prev->next = block->next;
 	block->next->prev = block->prev;
 	free(block);
+	
+	Unlock_state();
 }
 
 /** malloc() that doesn't accept failure.
@@ -233,6 +248,8 @@ void *Z_MallocAlign(size_t size, INT32 tag, void *user, INT32 alignbits)
 	Z_calloc = false;
 #endif
 
+	Lock_state();
+
 	block->next = head.next;
 	block->prev = &head;
 	head.next = block;
@@ -258,7 +275,10 @@ void *Z_MallocAlign(size_t size, INT32 tag, void *user, INT32 alignbits)
 		block->user = user;
 		*(void **)user = ptr;
 	}
-	else if (tag >= PU_PURGELEVEL)
+	
+	Unlock_state();
+	
+	if (tag >= PU_PURGELEVEL)
 		I_Error("Z_Malloc: attempted to allocate purgable block "
 			"(size %s) with no user", sizeu1(size));
 
@@ -392,6 +412,8 @@ void *Z_ReallocAlign(void *ptr, size_t size, INT32 tag, void *user, INT32 alignb
 void Z_FreeTags(INT32 lowtag, INT32 hightag)
 {
 	memblock_t *block, *next;
+	
+	Lock_state();
 
 	Z_CheckHeap(420);
 	for (block = head.next; block != &head; block = next)
@@ -400,6 +422,8 @@ void Z_FreeTags(INT32 lowtag, INT32 hightag)
 		if (block->tag >= lowtag && block->tag <= hightag)
 			Z_Free(MEMORY(block));
 	}
+	
+	Unlock_state();
 }
 
 /** Iterates through all memory for a given set of tags.
@@ -627,6 +651,8 @@ size_t Z_TagsUsage(INT32 lowtag, INT32 hightag)
 {
 	size_t cnt = 0;
 	memblock_t *rover;
+	
+	Lock_state();
 
 	for (rover = head.next; rover != &head; rover = rover->next)
 	{
@@ -634,6 +660,8 @@ size_t Z_TagsUsage(INT32 lowtag, INT32 hightag)
 			continue;
 		cnt += rover->size + sizeof *rover;
 	}
+	
+	Unlock_state();
 
 	return cnt;
 }
@@ -648,6 +676,8 @@ size_t Z_TagsUsage(INT32 lowtag, INT32 hightag)
 static void Command_Memfree_f(void)
 {
 	size_t freebytes, totalbytes;
+	
+	Lock_state();
 
 	Z_CheckHeap(-1);
 	CONS_Printf("\x82%s", M_GetText("Memory Info\n"));
@@ -677,6 +707,8 @@ static void Command_Memfree_f(void)
 	freebytes = I_GetFreeMem(&totalbytes);
 	CONS_Printf(M_GetText("    Total physical memory: %s KB\n"), sizeu1(totalbytes>>10));
 	CONS_Printf(M_GetText("Available physical memory: %s KB\n"), sizeu1(freebytes>>10));
+	
+	Unlock_state();
 }
 
 
@@ -698,6 +730,8 @@ static void Command_Memdump_f(void)
 
 	if ((i = COM_CheckParm("-max")))
 		maxtag = atoi(COM_Argv(i + 1));
+	
+	Lock_state();
 
 	for (block = head.next; block != &head; block = block->next)
 		if (block->tag >= mintag && block->tag <= maxtag)
@@ -705,6 +739,8 @@ static void Command_Memdump_f(void)
 			char *filename = strrchr(block->ownerfile, PATHSEP[0]);
 			CONS_Printf("[%3d] %s (%s) bytes @ %s:%d\n", block->tag, sizeu1(block->size), sizeu2(block->realsize), filename ? filename + 1 : block->ownerfile, block->ownerline);
 		}
+		
+	Unlock_state();
 }
 #endif