• Thanks again for the advice in this thread on the TH3 Cakewalk, especially scook, you were more than kind. This is what tech support had to say at overloud:

Hello John,

 
TH3 Cakewalk should work inside SONAR without asking for authorization nor entering demo mode. 
 
If it does, that happens in one of the following circumstances:
 

• You are using TH3 Cakewalk inside a version of SONAR that is prior to 22.04.
  Only SONAR version 22.04 or above supports TH3 Cakewalk.
  To check your current SONAR version, click the "Help" menu in SONAR and choose "About SONAR".
  The version number will be displayed in the bottom left corner of the window that appears.
  If the version is older than 22.04, you can update it either using the Cakewalk Command Center that is installed on your computer, or by downloading the latest installer from the Cakewalk website, after having logged in and clicked the "My Products" tab.
  
  
• You are using TH3 Cakewalk inside some other DAW that is not SONAR.
• TH3 Cakewalk is designed to unlock its content only inside SONAR. If you use it inside some other host DAW, it will behave just like a regular installation of TH3, i.e. it will work in demo mode unless authorized.

 

• You have tried to use some effect that is not included among those available in TH3 Cakewalk.

•  In that case, TH3 will prompt you to authorize in order to "unlock" the model or preset that you have tried to use.

 
 
I was guilty of the 3rd one down on the list. Boy is my face red. Seems to be working as it should now.

scook
Did you remove/rename %appdata%\Overloud\TH3 before re-installing? If not, I suspect the plug-in will stop working. The image refers to activating the FULL version. TH3 Cakewalk requires no authorization and does not run in demo mode. It is possible to launch the full version demo mode from TH3 Cakewalk though. It is not clear if you are really running the full version demo mode or confusing TH3 Cakewalk as the full version demo mode.

Hey y'all, 
   Not to bring up an old thread but...... after installing early access 2017.05, I now have this problem (I ended up with TH3 full version & it wants a serial# to activate).
   So.....I searched the forum & found this thread along with a couple other similar threads.
   I followed Scook's instructions as above, first deleted the folder, then I re-installed 'Engineering FX Suite' from the command center.  I still end up with TH3 full version.
   So I again deleted that folder (TH3) and this time I re-installed 'Boutique FX Suite'. I open SPlat and discover I ended up with TH3 full version again!  Ha!   

It just crossed my old brain that I haven't actually opened TH3 for several months, so this switch to the full version could have happened sometime B4 the early access 2017.05 update.  

Anony, check out this thread for the answer:
 
http://forum.cakewalk.com/Ive-Been-Checking-Out-the-May-Early-Release-m3610725.aspx

Thank you Pat, I had already read that.
I did figure it out though.  The first time (In CC) I had clicked to re-install Boutique FX Suite, that was wrong.
The next time I right clicked on Boutique FX and then clicked "roll back to 2017.05"  -  This worked. Now I am back to 'TH3 Cakewalk'
 
Thanks guys