Issue upgrading from AI to 8 Pro


I’ve just bought this:

It says: “Please note that this bundle includes an upgrade to Cubase 7.5 from the Cubase AI included with the UR22. Upon registration you will automatically be upgraded to the NEW Cubase Pro 8”

I’ve installed Cubase AI (from the download code included) and it turns out it has installed AI 8.
I then activated it successfully.
I then installed Cubase 7.5 from the included CD.
When I went to activate it I entered the activation code included with the CD, but then the attached screen appeared and didn’t let me pick any existing license to upgrade.

Please can you help me to get this working? Thanks!