Railworks America

I read the tutorials, Ive done some research and did another attempt to even try and comprehend something about it. But I just don't get any of it, do you have to be a rocket scientist to know how to make skins in Railworks? I've skinned for a few other games and it's fairly straightforward, open .dds document (or .bmp file if the developer is kind enough to provide it) edit it, and resave it. Between the programs I have to get and edit some code and all sorts of other stuff that makes about as much sense (to me) as flying pigs, I find that theres multiple skin files for one model! How do you guys do it!? I'm going crazy because of all the locomotives that have terrible textures like the 4-4-0 and the 2-8-0 and the default skins for all the britkit models and I'm just stumped (and extremely frustrated)...