At first I thought that the switch to toggle the NAV/COM frequencies wasn't working.  After closer inspection, the button is working but the highlight isn't switching between COM and NAV.  The frequencies can be changed but the lighter blue shading isn't changing between the 2.

 

John Navara

That is not the behavior I am seeing, are you perhaps running more than one window open with the GNS unit displaying in them?

My bad.  It's working fine in the A2A Comanche.  I was having the issue using it in the Carenado King Air based on the panel.cfg file I found in reply #7 located here:

 

http://www.avsim.com/topic/449772-pop-up-in-carenado-kingair/

 

Thanks,

John