Material refresh

I have one model which doesn't import very well. I can export it and put it in a new project and every mesh has the right materials. But in my main project the material ids are wrong. The model works in every other project but in this one, does anyone have an idea?

Import unitypackage from functioning new project: old materials are there, new materials with xx - default are generated.
Import fbx with textures in Materialsfolder: Materials are named xx - default but have those textures (wrong ones)
Import fbx with import materials set to false: old materials (with wrong textures) are used
Import fbx with import materials set to true and textures deleted: 50 white xx - default materials will be imported
Import fbx with import materials set to false and old materials deleted: 50 white materials with material names from the model are generated.

The same with a deleted library and everything reimported.
The wrong textures are always the same, it's not random.
I have an fbx and an obj file, both don't work. Both have the same wrong textures...

If I set material naming either to "by base texture" or "from model's material", I'll get materials named "ModelNameMat", even if base textures have different names.

 

Is this 5.3 beta specific? This really isn't a bug reporting forum for general issues.

Do you have a bug report you can share?

 

The same model worked in 5.2, so I think it is 5.3 related. I don't have a bug report yet since I can't reproduce it in another project. The faulty project consists of about 55gb of assets, so I can't send it to you fully without finding the faulty spot..
I am currently copying the whole project to delete it file by file until I maybe know what the problem is.

 

It isn't unity 5.3, it's morph3d.