I've installed Sonar Premium, and after that ran my purchased CA-2A installer.
 
The CA-2A is available as a VST3 plugin, but NOT as a Pro Channel module. All my projects are opening up saying the plugin is missing, and I'm assuming I've lost my settings unless I can get the Pro Channel version back.
 
During the install there's no option to choose Pro Channel.
 
Thanks in advance for any advice!

If you did not install the VST2, I would give it a try. I suspect the PC module is just a special call to the VST2 dll.

I have the CA-2A in Pro Channel. Maybe you have to reset the plugins in the preferences menu and rescan your plugins.

I also have a CA-2A in the ProChannel. I'd bet either scook or cowboydan has provided the answer.