[0.90.4] Crash when trying to overwrite a save file in town

[kharmadillo]

Had this occur 4 times now, twice in 0.90.3 and twice in 0.90.4. Whenever I try to overwrite a save file in a town, after building a research bench, the game crashes. Not sure if the town/research bench part is relevant, but it doesn't seem to happen anywhere else apart from towns.

The game also deleted one of my saves from 0.90.3 when I downloaded 0.90.4. It feels like the game just doesn't want me to do anything other than make my squad run to Mongrel over and over...

Also, I'm getting woefully bad framerates. It takes about 5-10 minutes after loading up a save for my game to actually reach a playable framerate, and even then it's erratic between over 60fps and below 1fps. Don't think it's a hardware problem as my PC can run new and graphically intensive games at max settings.