I find using a single 'Group' and placing all the ui-items (widgets) inside it works best for me.
Here's an example of my dashboard for viewing Wildfires around the world.
EDIT:
Just re-read your post about the "dynamic" action.
I've never tried to do that and don't know if NR is capable of doing that.
I'm sure someone else will jump-in and help.
Just found this posting - looks like you could modify the code to do what you require.