Blender is complete Coo Coo with exporting FBX.
I cannot export that object without hetting as present one extra texture added.
This is how it looks before exporting it to fbx.
After reimport the fbx in blender it looks like this, and i get one free roughness map.
@Menithal and in this case it’s not a wrong path / directory problem with a texture.
I can really not find any sign of where the 4th texture would coem from, it can only be some bug in the exporter.
The only problem could be the workflow Blender -> fbx -> 3D-Coat -> OBJ -> blender -> FBX. I can try to dump all materials and textures and reassign them from scratch in blender.