Clay Doh works with Blender’s Asset Browser. There is no Addon to install.
In Blender, open an Asset Browser window. (Or change any window to an Asset Browser type using the button at the top-left corner of each workspace window).
Once inside the Asset Browser, you will see a slightly bigger drop-down button at the top-left that lets you choose asset libraries. Click on it to see the list of available libraries, and select ‘Clay Doh’ from that list.
Now you will see all the Clay Doh assets in the Asset Browser. Make sure to set the Import Method to ‘Append’.
Everything is sorted in catalogs here, simply drag-n-drop. :)
Geo Nodes: nodes that ****can be dropped in the ‘Geometry Node Editor’ window.
Material Presets: materials that can be dropped onto models in 3D Viewport.