BobF
Just grabbing at straws here, but maybe CTRL-F5 to refresh your account page will do something 
That didn't help. I poked around some, expanding all the displayed products and such. Nothing seemed to work.
I'm curious, if you go to your Cakewalk account, my Products / Platinum and looked at the bottom of the list for Local documentation, does it show version 15 or 16? It may be that CC is the only way to get it right now