Unable to get scenarios to play

[wants to know]

I can't get scenarios i download to play, the main ones i'm trying to get to work are The Great War 2.1, and WorldWar3. Don't remember names or such but if anyone has played these can you tell me how to get them to work. I can get them to open and start, but after i choose the civ and the configuring scenario bar pops up the game freezes and i have to exit the program, i really would like to play these scenarios but am unsure how to get them to work.