Hi Andrew, also re:

> I do not understand why I can save the CAD drawing as a region in dxf format but cannot open it in
> MoI. Can't MoI extrude regions brought in from a CAD drawing?

Sorry I think I originally didn't understand this part - are you referring here to the Region AutoCAD entity?

MoI will currently read line, circle, arc, point, lwpolyline, polyline, ellipse, and spline entities from .dxf files. It doesn't try to process Region entities. If you have an example file that is not working please post it or e-mail it to me at moi@moi3d.com if you wish to keep it private so I can take a look at it.

- Michael