I am trying to access the PX64 module chain which is in Sonar Platinum.  I have look in pro channel presets, various FX chains, and used F1 for help.  Sorry to bug you more knowledgeable users but how do I access this?  TIA

The PX-64 Percussion Strip is part of the Boutique FX Suite. Do you have that installed? You can check Command Center if you use it, or your Cakewalk account.
 
https://www.cakewalk.com/My-Account/Product/CSPT100?connectedProductId=31
 
You can also try searching in your Sonar plug-in browser for PX-64.

According to my Sonar Instillation Center, I have it installed.  It is installed along with Breverb etc, so is it a Pro Channel?  The videos I was watching showed it as an EFX chain.  It seems to be installed, how do I access it?  TIA and I appreciate your time and the reply!

It's not part of ProChannel, but you can use it in ProChannel as part of an FX chain.
 
https://www.cakewalk.com/Documentation?product=SONAR&language=3&help=ProChannel.10.html
 
You should be able to insert it like any FX plug-in. Did you try searching for it in the Plug-In Browser? I can't tell you exactly where to look there because there are different layout options, but I think by default it's listed under Channel Strip if you sort by Category - not 100% sure on that.
 
https://www.cakewalk.com/Documentation?product=SONAR&language=3&help=Browser.07.html
 
 

Got it.  Figured out to look for it as a Cakewalk plug in so changed to sort by manufacturer and there is was.  Much thanks for the help!

Don't forget the search option above the plug-in list. Type "px" and it should show up regardless of the sort options.

I am returning to Sonar after a long long layoff with music.  I did not even know about the search feature!  Thanks!