Export problem material texturemapping with FBX/obj/sketchup

I have a problem with textures when exporting objects. If I export an object as FBX e.g. to twinmotion, the texture mapping is not correct anymore and multiple subobjectmaterials of objects/surfaces are not exported. I have tested here for a few hours and also other file formats like .obj and sketchup.
When I look at the objects in 3ds max, they look as faulty as in twinmotion. If I export an object from 3ds max as FBX with multi-subobject material it works.

It was a little bit of a learning curve but I made some mistakes: bigest mistake is that I didn´t set f.e. the bounding ox in mapping channel properly. Now everything works fine apart from export multi sub surfaces in one objects. It would be great in the future if this will work for mesh objects too. Or is there any other way of how to export with multisub surfaces on one object without exploding the object?