Done/Return/OK in mapkey

That made sense years ago (pre-WF1) with the old cascading menu interface, but likely won't work now.

Back then, in some situations the command was Done, some it was Done/Ret, Done / return, Done Sel., Done Select, etc. You needed every option in your mapkey in order for it to work universally.

Now, the 'Done' command includes some info on the dialog box it lives in so I doubt you could create a universal mapkey.

The reason for doing this was to ensure that the working environment was returned to a known condition - the root or top level for all operations.

The equivalent now is "Window/Activate" or Ctrl-A. It doesn't complete commands, it interrupts most commands, so use it only to (mostly) reset to the nothing selected/no operations pending condition.