Model becomes semi-transparent when exported from Milkshape

[Arkan.]

Okay, I have a really weird problem. I made a model in Milkshape and exported it using msWCMDLExporter.dll (I tried two different versions, same happens), and when I open it in Magos Model Viewer, it appears all glassy and semi-transparent (look attachment pic). I'm using the Naga Myrmidon texture if that makes any difference.

What the heck is going on?
This only happened on my most recent model, and I can't figure out why and what's causing it. I compared the .mdl file with my previous ones and they are identical except for the vertices/triangles part.

EDIT. NVM I screwed up with backfaces, they appeared as white in milkshape for some stupid reason.