Hi citroelf - Rhino can store many different kinds of data in 3DM files, like NURBS objects, spotlights, annotation text, dimensions, polygon mesh data, etc... Of all those various kinds of data, MoI itself is only focused on working on NURBS data.

That particular file that you posted does not contain any NURBS objects in it, it only has a polygon mesh object in it. That's why nothing shows up for it when you open it up in MoI.

Polygon mesh data is structured differently than NURBS data, it's made up of a lot of little individual facets rather than large smooth surfaces. You usually need to use a polygon mesh editing program to work with that kind of data, not MoI.

For this particular kind of case where it's an actual faceted model (instead of several hundred thousand little tiny facets trying to approximate a smooth surface), you could use Rhino to convert the polygon mesh object into a NURBS object which could then be loaded into MoI. To do that, open the file in Rhino, and use the MeshToNURB command to create a trimmed planar NURBS surface in place of every polygon facet. MoI will then be able to read in the converted NURBS object.

- Michael