You’ve successfully unlocked Cubasis LE since you’ve seen the pop up message, after connecting a compatible device.
In addition, you can choose to register your Cubasis LE app version and get a free RoomWorks SE plug-in via the Cubasis LE in-app shop.
This is unrelated to the Cubasis LE unlock procedure.
If you encounter problems using the app, please file a detailed bug report with a short step description, to allow us supporting you.