There seems to have been an issue with the account registration system for the paid downloads that should now be resolved.
I would like to apologize to everyone for the issue here and to back what Terry said with regards to the availability of the community edition (and that the community edition may be used with a commercial license). Regardless of whether you were able to activate your account, rest assured that your license was valid from the time of purchase and covered your use of both the community and commercial editions, and that there are no features unlocked in the commercial edition that are not available in the community edition, licensing status not withstanding.
Thank you for your patience and understanding.