Hi Get Root,

you wrote:
> it is precisely this .stl format that is giving problems

You wrote ".stl" format, which is a different kind of format, did you mean .stp format?

From the look of your screenshot it could be possible the model is malformed in some way such as pieces of it are overlapping back on top of themselves or something along those lines. If that's the problem then those problems would probably need to be fixed first before doing the export to any format.

But you could also try any of STEP, IGES, 3DM, or SAT file formats, those are the CAD file formats that MoI supports for transferring NURBS surface data into MoI. But if the data is malformed at export or conversion time out from Fusion360 then you can't expect MoI to import it well no matter what format you use. Sometimes it can be good to test the file with a variety of different CAD programs to see if any other program can read it in better or whether it's messed up in all other programs as well.

- Michael