I like the Sponsor and the design. However i feel something's missing to make it a complete Skin. The back of the car is very empty, especially the rear Wing. Maybe you could add another sponsor or a Start number there. I'm not too sure about the front wing either, imHo it would look better without the black/white pattern on it.
You can't just slap on the decals over the side of the car like that, on various places they have to be aligned and properly connected over the various parts. Visit http://www.lfs-gear.com/kitz.html and get the skin kit for the fbm. You can open the .psd files with photoshop, paint shop pro or the gimp for instance. Once you study those it will start to make sense more