While getting ready for a Show at home with 2nd Display attached, the
Singers display window just disappeared 

, as if it is no longer a part of Hoster.

I checked Hoster's settings first & nothing has changed. Then I checked display settings on my laptop & also nothing has changed. It is still set for dual display, which is showing correctly (and not cloned) because only the desktop background picture shows without the icons.
I can undock & move the Preview Window over to the display monitor so the singers can still see the words (if I have to), but the Marquee & SND still display the words as small as if it is still docked on the Playlist, so I just wouldn't be able to use those features
This is the same laptop I have been using for 7 years. I never heard of this happening to anyone before.
ANY IDEAS
Have a Show tomorrow.