Very strange behavior. If I add an ATC button with no properties set in the ATC dialog it will allow the button to be added. Then I delete the ATC code, refresh, select 'Yes'.
At this point I am able to add an ATC button with all my required properties set.
But everytime I tried to add the ATC button, while setting Bindings it rejected the add until I added a non-Binding button, delete, and refresh. Weird.