[fv]

after many testrounds and hours I found the cause for my problem where a material simply would not convert into a Maxwell material. All was absolutly ok but still the material would not convert. I then deleted the matrial in Skechup and made a new one and reassigned the material to the geometry.

In Sketchup once you have assigned a material and named it you can no longer change the name. The original name will be there indefinatly no matter the new one. Somewere invisable to the user the old name remains the trigger for the conversion.

So I deleted the materials that gave trouble and made new ones and reassigned them. Then it all worked again.
The problem was in the Sketchup part of the process.

[fv]

and it was not a matter of a typo. I had name the mateerial 12 to make sure there was no mistake about the proper and same names.

[numerobis]

using auto mxm you can rename your material without any problem.