Interesting.
The UV's are very stretched on some areas of the model, and from the black areas around the muzzle and on some other bits, it looks like you've got some screwy normals.
Overall the model is ok (although getting all those guns to fire in FPSC is going to be nightmare). The texture itself needs alot of work, at the moment it's very flat, with no definition on the corners. It looks fine in your modelling application becuase the app is adding default lighting effects to it, once you put that in FPSC, where there is no decent self shadowing, it's going to look flat and horrible, furthermore, those black sketchy normal bits are going to come out like that in the game.
I want robotic legs.
