Hi TKnudsen,
I suspect that you are trying to install the Add-on on an Intel Mac. Please note, that the AI Engine of the Add-on does not run on Intel Macs.
You can install Stable Diffusion server ('sd.webui' folder) on an Apple Silicon device and specify the address of this server in the AI Visualiser UI on your Intel Mac. The Intel device will send requests to the Apple Silicon one (set as the server) and you'll get the result in Archicad. In order to make this work the mentioned folder should be added to the Archicad27/Add-Ons/Extras folder on the Intel Mac.
In case you are trying to install it on an Apple Silicon Mac please contact your local support.
Kind regards,
Norbert KucsmaTechnical Support Engineer