Hi Tom, what's happening there is that 3DM files can actually contain both NURBS and polygon mesh data in them, it's kind of a combination file format.

However, MoI will only write NURBS data to the 3DM file, and Cinema4D will only read polygon data from the 3DM file. So they're kind of like 2 ships passing in the night in this situation.

Even though LWO works, I would really recommend OBJ format for going from MoI to Cinema4D - the OBJ format will also bring smoother shading information (vertex normals) into C4D which helps to increase render quality.

LWO is best for going into Modo or Lightwave.

- Michael