Anyone experience this? It shows up in the plugin browser, I put it into my preset folder, but when I go to insert it, only the mono versions are available?

Very weird.
 
I'm just full of complaints today...

Might be the odd sonar naming idiosyncrasy that I experience here and there with certain plugins. What I do is rename the dll: try with spaces, without spaces, may be an underscore, abbreviate it. Then rescan of course. This usually works for me.

You should have two option for the UAD plugins.
Under VST2 you get Powered Plugins.
Then you should have Mono and UAD - Powered Plugins
If you want mono you select the mono and find the Fairchild. Works on my machine.
I did notice a change to the Audio FX has no arrow to its right you have to click and then you get a new box with the arrow. Is this intentionally or a bug?

Usually this happens when the plugin in the menu has been replaced by a newer version. If you right click and select properties in the menu layout (on the right) inside plugin manager and get blanks it means the plugin is no longer there so it doesn't show up in the menu inside Sonar.
 
Just delete it in your menu and re-add it and you should be good to go.

Thanks very much, I will try those ideas.