I am trying to revamp the old fuel rod gun (not the plasma cannon; the one wielded by grunts). I'd like to make it an usable weapon, but it really lacks in detail. I am thus trying to open it with 3ds max and make stuff there.

What I did:

[*]GBX model importer to import it[/*]
[*]Fixed the position of markers (they were actually scattered around, for reasons that go beyond my knowledge)[/*]
[*]GBX model importer broke the old shaders; the fuel rod gun had 4 shaders before importing: fuel rod dull, fuel rod metal, fuel rod ammo and fuel rod case. On importing, the latter 2 got all assigned to fuel rod metal.[/*]

I am then trying to restore the original shaders, but it seems that I am not assigning the materials properly.

How I assign materials:

[*]Open the material editor and go to multimaterial[/*]
[*]Add the 2 new materials, fuel rod case and fuel rod ammo[/*]
[*]Set this new material to use the default fuel rod gun bitmap as diffuse map[/*]
[*]Via "Editable Mesh/Select elements" I choose the elements I want to assign to this new material[/*]
[*]In the material editor, choose my material and go to "Material => Assign to selection[/*]

It's all nice, but there are 2 problems that tell me that something is going wrong. First, the elements that use my new materials are now grey =| and second, if I choose an element, in the editable mesh, I can change its material from 1 to 2 if it has material 1 or 2, but my two new materials are not in the list. If I assign the material 3 or 4, on the other hand, in the list of materials in the editable mesh appears only such material, not the others (if it is 3, the list only shows material 3, and same goes for material 4)

That's a step-by-step of what I did, no passage was skipped (I think), so that any error will be clear. Thanks for reading!

Uncheck "Attach Parts of Mesh Within Region" under Model Geometry Options when you import.

... It was much easier than expected. Thanks lol

Sometimes it is.

Use my modified gbxmodel importer next time. it imports all shaders and can also import xbox models.

http://chief-01.deviantart.com/art/GBX-XBOX-Model-Importer-v3-6-0-493742952