If you load one of your save games, does this reproduce for you? Can you please go to Documents\My Games\GC3Crusade (or GalCiv3 if you don't have Crusade) and zip your Prefs.ini, your debug.err file, and a save game and post it on a cloud drive for me? If you have a way to record a video of this happening, a link to a video may be helpful also.