Twinmotion and Presenter Materials problem

Twinmotion material problem, i desperatly need help.

I have two materials problems since weeks now and i don’t find a solution. (i think that the problems are linked).

The groups / components are not painted in sketchup, i checked this, I only paint the faces of the object. I’ve hundreds of sketchup materials in my model, all have different names. I tried from a totally new empty twinmotion file :

When i import my sketchup to twinmotion project (datasmith of livesync), some of my material are replaced by others of by “default material”… First problem > From where does it came from ? How to solve it ?

So i correct it in twinmotion, re-assign the good materials, then i export from the twinmotion corrected model, a twinmotion presenter file (interactive virtual tour standalone). Now some of my material became what they were before the correction, others became what they were in the sketchup file, and some (like in the image example) are replaced by totally other materials (different from the original twinmotion replacement that i have corrected)… Second problem > From where does it came from ? How to solve it ?

Some informations : I tried to delete any group / components texture in sketchup (to keep only the faces textures). I tried to explode the problematic groups, then group it again. I tried to change the textures names. I tried to simplify the hierarchy levels. nothing has worked so far.

Its been two week that i try to find answers… it gives me hard headaches. If someone have an idea, it could help me a lot. Thank you for reading. I wish you all a good evening.