I have a top and bottom panel, configured to auto-hide.
- - when I move to the bottom of the laptop screen, the panel doesn't stay open (close/open/close/open/close/...).
- when I move to the top of the Dell screen, the same happens (except the "bottom" panel is showing up at the top, which actually works fine).
- on the Dell screen, the panel shows only the windows that are open on that screen (good!).
- if I disable auto-hide, the panel shows only on the laptop display (so I don't get a panel showing only the windows on the Dell screen).
- if I switch to a side panel, it shows only on the laptop display.
I found that it's possible to access the panels using keyboard shortcuts. That will probably be workable, though the selection seems to be a bit funky (cycling between top/bottom/desktop doesn't work like alt-tab). See e.g. http://community.linuxmint.com/tutorial/view/45