Rhino 7.9 update issues with ue4 and lumion

After the latest updates a lot of programs which used to synchronize with Rhino stopped working. 2 of them is Lumion and Twinmotion (UE4).

For some reason when you have 2 or 3 materials on a polysurface, Lumion & Twinmotion recognizes only 1 of them. And the only way to have multiple materials on a polysurface is to explode it into multiple surfaces.

Previous Versions of Rhino were running smoothly and you could add as many materials you like on a polysurface without the need of exploding it and Lumion would recognize them. What happened in the version 7.9 and is unsupported from all the rest software that used to work smoothly with Rhino?

Btw I’ve tried this on 3 different computers and they all had the same issue with Rhino version 7.9.

A colleague of mine who has Rhino version 7.1, Lumion & Twinmotion works smoothly with no any problems so the problem is clearly from the updates.