I have several 3D files built in Microstation V8i SS2, that I need to convert to 3DM in Rhino 4.0. In theory Rhino opens the .dgn files, but in reality it misses out elements, drops solids to lines and creates triangulated meshes out of what are, in Microstation, square blocks. Is there some way of getting around this in either Microstation or Rhino?