When you change gamedirs, cachepics (such as your conback) will be reloaded

in GL..  Please test this extensively, I _think_ the tempfile loader is
smart enough to handle what I'm doing properly.  If it's not, we'll have
to fix a slight memory leak.

source/cl_parse.c

@@ -542,6 +542,8 @@ void CL_StopUpload(void)
 =====================================================================
 */
 
+void Draw_ClearCache (void);
+
 /*
 ==================
 CL_ParseServerData
@@ -578,6 +580,7 @@ void CL_ParseServerData (void)
 		// save current config
 		Host_WriteConfiguration (); 
 		cflag = true;
+		Draw_ClearCache ();
 	}
 
 	COM_Gamedir(str);