Hi Andrei,

> Michael have this problem, that practically do not allow me to Paint, Retopo and UV in 3D coat..((
> http://3d-coat.com/forum/index.php?showtopic=14850

Sorry, I don't really know what's going on there, from what is described in that thread it seems to be a problem specific to 3D Coat that it's sensitive to certain kinds of geometry.

Did this happen when you exported using N-gons? If so then try exporting using "Quads & Triangles" instead of n-gons, it's not all that unusual for programs to have some difficulty processing complex n-gons and make bad triangulations when it has to convert them.

- Michael