I don't know I how can I help you sincerly. I'm a decent computer programmer (not so close to machine as some of you, more a php high level, than a bit to bit low level programmer), but a TERRIBLE graphic and I really don't know how to click when it come to use GIMP for something that isn't simply "change a color here and there"
The best I cand do, for now, is continuing to have some experience in campaing creation, trying to figure out things aren't documented yet (like all the damn event id that if known can completely change the power of our IA units).