straycat_07@yahoo.com
If they aint already, BMP format 256 pixles square. 512 works too.
Mapping's not hard, just takes alot of time & patients. The editor isn't all that stable and likes to crash alot. You learn to save your progress alot. I have a basic how-to-map if your interested. It tells you enough to get you going, Unreal Wiki can help with most questions.