Game Crashing on Phillipines Mainland Assault - Allies

[SpotnOptimator]

I'm consistently getting Stack heap errors and then the game crashes.
I'm running the following:
Version 1.83 of the game
AMD FX (tm) 4300 quad core processor
32 bit windows 7 OS
8 GB RAM
AMD Radeon HD 6670
Game is pretty much unusable at this point. This is my first time thru the campaign(Allies).
Thanks,