VocalSync Editor keeps vanishing - normal?

Hey folks - 
I've recently started working on some vocal tracks and I'm using VocalSync. Having made a clip selection, and added the Region FX, the VocalSync Editor window has a tendancy to vanish if I click on almost anything else, like:

• a track's SOLO button;
• reposition the NOW time;
• just click on an empty zone in the Clip Pane.

Is this normal? How the heck do I get the VS editor window back?
My workaround has been to "Remove" the region FX and re-apply it, but this doesn't feel right.
 
SONAR Ipswich (but I rolled back to H just to see if the problem was still there - and it seems to be)