Just wanted to drop in to say this to SE:
I bought the game, got the email with the link to get the code.
I go to the page to activate the code and on that page the instructions basically tell me to download the full version installer. This will effectively make me uninstall the whole game and re-download it, which seems nuts.
Instead I thought I'd try my luck in the MOG station and lo and behold, it let me upgrade there.
So silly