This add-on uses the rhino3dm.py module (https://github.com/mcneel/rhino3dm) to read in 3dm files.

This add-on works with Blender 4.2 and later.

On Windows and MacOS you need to download the correct ZIP archive from https://github.com/jesterKing/import_3dm/releases/latest .

1. Download ZIP archive
2. Open Blender preferences
3. Open Add-ons section
4. Click Install... button
5. Select the downloaded ZIP archive
6. Click Install
7. Enable the add-on