ver.3.50.1177 I was using laptop with external monitor for a while in "extended desktop" mode, moved NetPeeker windows to the external monitor, then disconnected external monitor. NetPeeker windows stays outside of the laptop screen and I could not find a way to get access to them. Finally, I connected external monitor again, move its logical position around until I can see the NetPeeker windows, move them to the main latop screen, then disconnect external monitor. Now I can access NetPeeket windows again.
Some method to force all NetPeeker windows to the main screen, accessible if they are not visible, would be very helpful in this situation.