Originally Posted by midwan
To switch between the different versions, I kept 3 folder names in my system: MUI38, MUI39, MUI4. The Assign of MUI: points to a folder named "MUI", so I would simply rename the folder of the version to test each time to MUI and reboot. No other changes were made to the system while testing and I always followed the same steps.
So you did not delete the old MUI configs in your envarc: folder?