I recently managed to get myself rid of this bug, turns out that the High definition mod 2.0 is not compatible with the 2.03 version of Gal Civ 2 (thats what I personally think) I had this problem, and then I deleted this mod and everything was fine, I think it has something to do with the planet textures of the mod, as that seemed to be the most damaging of all, anyway so if you have this bug, check out if you have any planet modded textures, that might be the cause, maybe.