I get this message when I’m trying to create a username. Have tried several variations, but keeps getting this message.
you must register your Cubase 8.5 license with your mySteinberg account
This message will be replaced by a more specific info (very soon).
The issue is solved now in version 1.0.23. The message is replaced by a more specific information.
Nevertheless, registering your Cubase 8.5 license at MySteinberg is (still) required.