Materials problem when exporting to .obj

I have a very simple Cycles scene with some meshes. The meshes have multiple materials (each face has a different Cycles material). I’m trying to export to .obj, but the exported object has materials that are completely wrong. In some case the textures are missing, in some other cases I see the texture but the material is assigned to the wrong face, in some cases I loose UVs.

I’ ve tried Windows and Linux, different Blender versions, but I’ve always problems.

Do you have any tips and tricks? Are there known bugs? Is there a reliable combination OperingSystem/Blender version?

Any suggestion will be appreciated, I’ m getting crazy :frowning:

see this one

happy cl

Are you sure??
I don’t see how STL Export scaling is the answer to the problem here.