[Issue] Unable to create custom UVs for Model

[MissingTexture]

So I am trying to make custom textures for the Cato Neimoidia map that was released with SWBF3 Pre-Alpha models. But for some reason the model appears like this:

[spoiler][/spoiler]

Any reason as to why this is happening?

[Cdt Fox]

I have a similar issue with other swbf 3 mesh. I'm interested if anyone have an answer to that. I always used this method before and it always worked fine....exept for a few other weapons including this one. 

[spoiler][/spoiler]

Note: All the weapons that have the same issue are supposed to be the first person mesh. I never encountered this problem with 3rd persons meshes.