OK, thank you for information! After that fixing takes less than 5 mins, so here's the fix:
OK, thank you for information! After that fixing takes less than 5 mins, so here's the fix: https://www.mediafire.com/file/07zuzaj31z4w81m/Ki-49-II_shadow_fix.7zMesh has two materials and was copied as shadow. Thus, vertex indices are incorrect in [shFaces] with indexing for two materials. The fix is to add to all indices of second material 1+ the largest index of first material. I had MATLAB code ready for such modifications, but it shouldn't be too difficult with other methods either. Shadow flashed because of unused vertices.
I have two skins for this beautiful bird ...Those interested go to the skinshop page- Japan...
This can be rightfully called a real teamwork project, thanks a lot trent!