Caliber,
I believe I was able to recreate the crash that Ratchet_Expert is referring to. When you use the Plasma Force Armor option when you are the Soviets and you use the first tier orbital bombardment power, the game crashes. I assume the result is the same for the other orbital bombardment powers.
I do not know if you are aware of this, but I believe that that is the cause of the crash.
What I've been doing is using Mega Unit/Building, to work around it.
It should fix your problem with the crash.