Found the solution! Thanks for not answering.
But for all people that have the same problem in the future:
You need to validate your files (or something like that) if you have the game via Steam. If you have it on a CD, it might be necessary to do a re-install.
I'm having the same problem.. The option to view generated player faces is greyed out in preferences. I looked at the official SI-games forum and found a couple of other people that had the same problem as well, but I couldn't find a satisfactory answer that could solve the problem for me.
The...