Hi, new meshing software for conversion of triangular mesh into quadrilateral (or quad-dominant) is available for free on www.topologica.org ArtMesh application is at the stage of beta testing now. Software uses another approach than RETOPO or similar. Resulting mesh's topology is not as good as after RETOPO but all hard edges are saved in mesh. OBJ files are used for input/output. Edges with splitted normals and edges between different groups and textures are saved after remeshing. The remesher was initially developed for engineering applications, so for some models result will be a bit unexpected. Images with input discrete geometry and resulting quad mesh are attached to the post. I am one of the developers of ArtMesh and I will try to answer any questions ... Thanks