This add-on uses the rhino3dm.py
module
(https://github.com/mcneel/rhino3dm) to read in 3dm files.
This add-on works with Blender 3.3 and later.
On Windows and MacOS you need to download the correct ZIP archive from https://github.com/jesterKing/import_3dm/releases/latest .
- Download ZIP archive
- Open Blender preferences
- Open Add-ons section
- Click Install... button
- Select the downloaded ZIP archive
- Click Install
- Enable the add-on