I can’t complete the backup in step 1. I go into backup, browse for the folder, select it in the finder, save it, go to add a scheduled backup hit save and get an “Invalid path specified” error.
On stopping the server: quitting the Roon window only closes the interface. On a Mac the server keeps running behind it, which is why you still see RoonAppliance and RoonServer.
Look for the small Roon icon in your menu bar, at the top right of the screen near the clock. Click it and choose Quit. That stops the server properly.
If any processes are still there afterwards, open Activity Monitor, type Roon into the search box, and quit RoonAppliance, RoonServer and RAATServer individually.
One correction to the path we gave you, because it matters and it would have sent you to the wrong place. On a Mac you will have two folders with similar names. The endpoint files live in the server one:
~/Library/RoonServer/Database/Registry/Core/
Not ~/Library/Roon/, which is the interface rather than the server. Delete the files beginning with endpoint_ in that folder, then start Roon again.
Please let us know what happens with the Vision Pro after that.