Brilliant, thanks. Making a lot more sense now…
If you want to remove a bunch of flows from a layout, you can also select all the flows first then untick the layout - that removes all the selected flows from the layout in one move. There’s no hierarchy of links between flows/players/layouts so you can pick whichever one has the most “moves” to make and select in that panel.
The “token” to use is $LayoutName$ - if the wrong name appears, check the name of the layout on the setup page. I added a bordered text field (in engrave mode) to the part master page to make it appear automatically.
Brian