Bad vertex data & question regarding attachments

My model has bad vertex data. Now I’m not 100% sure what it means, but it seems to had something to do with UVW mapping and textures.

However I haven’t done any UVW Mapping yet since I might want to change a couple of things on the model. However I want everything working before I start the uvw mapping and skinning, so how do I fix this. In milkshape it looks like this:

Also got another question. Is it possible to use attachments to add lights and particles to a model. Note that this is for TF2 so lua coding it isn’t a option.
I already decompiled the bomb cart of TF2, but it seems that all the effects are done outside the .qc

Come on, someone has to know whats causing this.

Are any polygons off the UV space?

Nope, I also tried adding a UVW Unwrap modifier and creating a basic (messy) UVW map but that didn’t help.

Are the verteces welded?

I never really understood welding, but I used collapse.