...was quite confusing. Had to do a lot of trial and error and digging to get it activated properly. It feels like a total hack-job. It failed twice at first, then suddenly worked. I can't tell if the restart of Platinum, re-trying the Celemony registration Licenser, or something jacked up and maybe corrected in my Celemony account was the fix. Can this process be refined at all? 

http://www.cakewalk.com/Support/Knowledge-Base/2007013381/Melodyne-Essential-Installation-Instructions

Thanks! The installation was a snap. It's the registration that was confusing.

I don't recall any issues. Perhaps your firewall was interfering, or you weren't running Sonar or the Licenser as Administrator?