I need to have a rough layout in MoI from a 3D file that contains oil pipes. the file isn't CAD nurbs but a poligon mesh, so I want to import it as a 3d dxf file. But exporting from C4D or Modo seems not to work, there are no objects after opening the dxf in MoI. When converting obj to dxf in FormZ, I sometimes get closed edges which can be converted to planar in MoI.
Why are C4D dxf files not usable in MoI? there are 3 options in C4D, polyline, solid & 3D Face, I tried them all, but no results. Even a single cube won't import, but is perfectly imported in other SW.

Any ideas on how to import a poligon mesh in Moi, just for positioning and measuring the objects (and regenerate them as nurbs like that)?

tnx
wim