If you haven't already, please check to make sure all of your video drivers are up-to-date.
If, after reinstalling the game, you still experience the crash, please install the free utility program SmartException. You can find this in the free section of Stardock Central.
Once installed, let SmartException run and run GalCiv2. Go through the steps to produce the crash. When it crashes, SmartException will generate a report that you can send to gc2bugs@stardock.com This will help us to determine where and why the game is crashing for you.
For more information on SmartException, please see this link:
https://www.stardock.com/products/smartexception/