Hi i'm new here

and i just bought GalaCivi Ultimate Edit, so heres my problem i've been playing a skermish on a small universe against 5 opponents and 3 minor races, i'd been playing the scenario happily for about an hour then everytime I destroy an enemy outpost the games minimizes and then crashes. I'm playing on a dell inspiron 1720 running windows Vista as far as im aware it's got upto date drivers, and theres no mods on the game any help would be apresheated thanks ^^