Hi Michael,
I know you have said that it would be a lot of effort to create an importer for polygonal models,
or also to create a translator from polygons to nurbs.

Would it be as difficult to convert a model made up of quad and triangles into a set of nurbs, so that each face is a nurbs surface (tri or quad) ?
So all polygonal curved models would be translated as a serie of nurbs quads or triangle surfaces.