mondblut actually I've had the same problem with Fantasy General. but there was a guide on gog how to edit the DosBox settings. but neither Natuk nor PotWS are Dos-games ... tried the compatibility modes but nothing works, so I guess these games are unplayable to me. what a bummer.
Well, you could run them from inside a Virtual PC Windows XP installation if all else fails. I've replayed the 2005 Grimoire version under Windows 7 that way a few years ago.