Spearhead crash to desktop on start-up
 

I have MOHAA War Chest, Ive just completed MOHAA and breakthrough with no technical problems but spearhead will not load for some reason!!

I start the game like normal, then it goes to a beige/browny screen and sticks just before the 'EA games challenge everything' bit. Then crashes back to the desktop or sometimes to a small black box in the corner.

With no error messages and no settings have been changed between playing the other games and this.

help anyone?