I've just been playing around with the Cubase iC Pro app for Android with N6 and must say that using it to set up cue mixes is much more intuitive, faster and easier than trying to do it with the unpopular Control Room and the squashed up Cue Send rack on the N6 mix console.
For a start, all the faders are VERTICAL! - You just select the Cue Send you want to set up, 1 to 4 (although this should be 1 - 8 by now - we have been asking for this for what seems like years) and the app displays a vertical fader for every track that it is possible to include in a cue mix + one for the selected cue mix level itself. It is then simply a matter of switching on the tracks you want in the cue mix and setting the level and pan for each one.
This is how it should have been in the N6 MixConsole and Control Room.