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  Thanks for the info.
Does 0.5.14 still not fully quit on your Mac (=> f.ex. the window is 
closed, but Plex remains in the dock and the screen's titlebar still 
displays Plex)? 
(Plex 0.5.14 quits correctly on my Mac, RC2 did not)
If you have created your own Behaviour for Plex, please create an 
action in BCK > Action Factory running this AppleScript snippet:
tell application "Plex" to activate
Then, in BCK > Behaviour Factory > Plex > Default mapping, select that 
action for the event "On manual activation".
Best regards, 
Felix Schwarz
  Felix,
My Plex has always fully quit. I've never had that problem.
I followed your instructions, I created the "Start Plex" applescript behaviour, but still had the same problems with Plex not starting (only the first time).
Instead of having button "x" pointing to "activate myPlex behaviour", I simply pointed it directly to the "Start Plex" command. Then it works!
So activating the behaviour doesn't work, even though I did all the steps you wrote, but "hardcoding" the button to point directly to the applescript works.
Thanks 
Martin