The game crashed while I was playing as cardassains.

I was making a demand of 200 or something deuterium and 10 raw materails and offering membership to a minor race.
I also had no colonies.

We had a problem with a lot of corrupt images in the last release. The images usually opened fine in Windows, but the game would sometimes crash when reading them. I believe the problems were with race insignia images, so the problems would usually arise in response to diplomatic actions. As a temporary workaround, you can try removing all of the insignias except the ones beginning with ("__", e.g. "__default.png") and the Federation insignia, which we know is fine.