UVW unwraps don't "stick" when exporting

I've UVW unwrapped a couple of objects on my rig and the textures appear perfectly fine in 3DSMax 2018, and when I check the material preview in the Mudrunner editor it shows the textures that SHOULD be applied, but the meshes just show as grey.
I've had these meshes work perfectly previously with the same model, I've even gone as far as to remove all the UVW mapping and materials from the affected meshes and remapped them but still no joy...
Any Max gurus out there who might have a suggestion to try?

0_1518474111321_Untitled-1.jpg

0_1518475013942_Untitled-2.jpg

"" <Material
MeshParts="rear_windshield 0"
NormalMap="NormalMap__n_d.dds"
DiffuseMap="rear_windshield_UVW.tga"
TwoSided="true"
SpecularMap="DSpec__s_d.dds"
/> ""

last edited by Mexican_420

I recently imported some new meshes for my suspension componnets and may or may not have impacted the material IDs (some of the parts had over 50 subobject materials!), but I have since nuked the materials with "$*.mat=undefined" in 3DSMax. If i change the XML to use a different texture, that texture works fine. It's only the textures I've used for the unwraps that seem to be affected.

Make sure the material ID is set to 1.

Edit; I should have said 'in max'. Sorry

last edited by Tattoo

@mexican_420 said in UVW unwraps don't "stick" when exporting:

rear_windshield 0

If selecting all the polys and assigning material id=1 does not work ...

Could it be the name of the mesh itself? In max, you named it "rear_windshield 0" maybe it needs to "rear_windshield0" without the space after windshield. Usually spaces mess things up..

last edited by joemama

Hmm, The 0 might be the problem because if there is only 1 texture applied to the part, the 0 isn't needed.

Came up with a workaround, tired of messing with it instead of playing. Thanks for the input though, gang!