Any of this maps being altered or wrong can cause a bad looking result.
All items for the game but particulary CAS items have a lot of maps that make the final result. You need to re-share the files in order for us to help you with that. Regarding your new issue, it might be that this time the specular is the problem. Hi Monas, first of all, in the normal map the red channel is copied to the alpha and the green to the rest because it's the way to convert a 'Normal map' to a 'Bump map' (which is the game uses to read the effect, it uses a greyscale ranges of pixels rather than the bluish that you get directly from a normal map.
