White screen

Hello,
first of all, sorry for my bad english but it's not my language.
i've just bought a PC copy of hero academy but when i start it the window is completely white.
I can hear sounds, and i can even click, in fact i clicked on the tutorial and it started.
I managed completing the tutorial, because it became visible. I mean, the gameplay of the tutorial was the only visible thing.
 
Is there a way to fix it? 
 
Intel(R) Core (TM)2 Duo Cpu
E6750 @ 2.66 GHz
1,99 GB RAM
 
Tnx