Checked all materials in scene, then make all multi materials instanced ( not copy )
( if multimaterials copy , exporter make unique material then repeat same materials again again )
But still trying to understand why few meshes upside down, i ll try append in scene again
And still cant see progress bar and full exporter screen
( My wish; for exporter screen , a checkbox for try to optimize all meshes in scene )
Thanks for your quick responds and interests
Hv nice works , tc. yourself
Kemal UÇAR