Sonar X2a - 64-bit. 
 
When I try to use TH2 Producer, I can use the presets fine.  But if I try to add a stomp box or something else, I click on the spot I want to place it, and I get a popup to choose from, but when I move my mouse, or press any other key, the popup disappears!   Has anyone else experienced this ?? Any fix? 
 

Disregard... As usual, a totally ridiculous solution.   My window was sized too large.  I guess this effects the pop up.  When I resized the TH2 window down more... it works fine.  Sorry.