In some situation I basically use the advanced output as a switcher: Sometimes the whole composition goes to projection1, sometimes to projection2, sometimes to both. For that I'll simply use the tick-box in the outputs list.
It would be helpful to get that one midi-assignable!
a little bug: when I use more then one external display (3 in total) then Resolumes numbering of the displays doesn't match windows numbering. In my case:
Windows display no 1 -> Resolume display no 3
Windows display no 2 -> Resolume display no 1
Windows display no 3 -> Resolume display no 2
Shared/exclusive port is of no issue between QLC+ and Resolume (which I have resorted to in the meantime).
Means at the moment only problem is: localhost missing as possible ArtNet host / IP Resolume sends to.
However, all of the above applies for R5.1.4 only. In R6 I can't get it to work. Everything looks as you wrote, Oaktown: in Resolume there is IP "127.0.0.1 (QLC+)" and in QLC+ I see Resolume's node, but QLC+ doesn't receive anything. Oaktown, was it working for you? With Resolume sending and in QLC+...