App Layering: Upgrading to 4.6 Fails to Complete, or Shows Database Errors, or Shows No Layers or Icons

While upgrading to version 4.6, the upgrade does not complete after several hours. If it does complete, after logging in, you see no layers or imag templates. And you will see errors like: "System Error - ComponentActivator: could not instantiate Uni.Appliance.PersistenceLayer.Session.SessionScop...