ZeWolfie42 One other thing that Faerin brought up is, when you extracted the files from the archive, did you overwrite the original files from an earlier version or did you extract them to their own folder? If you overwrote the older files from an earlier version, then that
might cause the issue that you're seeing.
Extract the files to their own folder without making any overwrites to anything, transfer your saves and mapping file (if you use the patched mapping file that is) and try playing the game.
Also, try temporarily disabling your AV software and see what happens.