I don't know if this will help anyone here, but I had purchased Z3TA+2 and Rapture Pro in the GOBBLE sale, and neither would come out of demo mode inside Cakewalk or in standalone, even though I had installed it using the Cakewalk Command Center.
I tried using the Command Center to uninstall Z3TA+2, delete files, and re-install, but it did not help.
Finally went and downloaded the command center fresh from my account area on the web at
https://www.cakewalk.com/Command-Center and installed it over the old copy, and everything worked fine after that. I did not even need to re-install Rapture Pro. So, I was surprised the old one did not auto-update itself or tell me there was a new version, if that was the cause.
Then again, I did go backwards from a Windows 10 installation reverting to 8.1 recently, so I'm not sure if that timing fits or not. Still, it is worth a try if you are having issues getting those plugins to work.
Terry