How to "Nudge Selected Object" in Monitor

I've tried CTRL+ALT+[DOWN,UP,LEFT,RIGHT] as indicated in the documentation to no avail. I've tried it with a text object, clip and graphic in the Monitor area. Still doesn't work.  The shortcut for snap S does nothing. I've started new fresh test projects and I still cannot snap or align objects in the Monitor area. I mean, there should be a way to snap a clip to the centre in the monitor, right? Using elements 2019 by the way.