Thank you for attaching the DWG. I opened it in AutoCAD, BriscCAD and Rhino and it appears to have written a good file. Text is Mtext and Leaders are Leader object. But there is no 3D geometry, that I would expect from see in the image if your model.
So now I need the 3DM as well.
If you do not want to post it here, please email it (or a link to download) to email@example.com
What I need to test is the DWG/DXF export on Rhino 5.4 WIP for the Mac.
The “2004 Solids” flavor should produced solids and meshes in the AutoCAD export.
What you are showing in the image above and what I confirmed you have in the file, is consistent with using the “2004 Lines” or “2004 Polylines” flavor of export. In these configurations, surfaces are exported as curves, which is consistent with the file you sent for testing.
Thanks for your help.