Well, I go to advanced output where my slices are done. Then I select the Screen and associate it with "Display 2" - Close and save... I make sure the output is set to Advanced only, but the second display remains dead black... I can only see my composition on the second display when I select Fullscreen Display 2, but of course it only displays the flat composition. There's no way I can get the post-mapping one other than in the Advanced window.......
Thanks, now we know a lot of helpful things: that the secondary output is working and it's not your adapter, that resolume is outputting something ( otherwise you'd see the desktop ), and you're playing something to output ( otherwise both screens would be black ).
What happens when you reset the Advanced Output to default ( Presets > Reset To Default )?