Hi Allan, also MoI can export 3D curves to 3DM, IGES, SAT, and STEP file formats (SAT and STEP are new for MoI v2).

So you might look for any converter that can take curves from any of those formats and bring them into LightWave or Modo.

And also one other - you can export curves to a 3DM file and use the DXF converter here to create a DXF file with the 3D spline curve data in it.

So that's actually 5 different formats that you can get 3D curve data out of MoI...

- Michael