I've purchased a premium account, however, when I go to PogoPlug preferences it says account type: Free

I see there is a place to enter my premium license key, however, I don't know where to find the license key? I'm looking at the email receipt I received after buying, however, I don't see the key in the email nor can I find it anywhere else.

Also, can I use my license key for all of my devices I'll be using PogoPlug with (computers & photos)?