Hey SK,
thanks a lot for you imput! When I'm back home from work, I'll check and post the information here.
Actually, I have completely reinstalled my computer in the last two days and tried rendering the scene again, but it crashed again. Now I tried to completely re-create the scene but I'm not finished yet.
But anyway, I'll check in a few hours and come back here.

Thanks a lot and take care,

~Sassy~