This may be a bit OT as this is only tangentially related to Blitzkrieg but it's my best shot for an actual solution to this problem since both games run on the same engine as far as I can tell.

I've recently tried to run World War 1, the game starts fine and everything seems to be working until I get to the actual gameplay. At the start of a mission sometimes there will be just a black screen with the sound effects playing, other times only the map with fog of war covering everything and no units. If none of that happens and the mission starts up fine I cant move the units. I can select them but am unable to issue movement orders. And no the game is not paused.

Is this known as a problem in the Blitzkrieg series? If so please point me to the possible solution, I looked through the forums here, but didn't spot anything.