Magic Sheet Cue Lists

Could someone explain how the "Cue - Active" target can be used in a magic sheet ? I can't see any way of specifying a target, so I assume this can only refer to the master playback ?

You can't specify a target but running cues from a fader other than the master playback influences the "Cue - Active" objects.

What I would ideally like, for a show with multiple cue lists, is to have a magic sheet which displays, separately for those cue lists:

1. Active Cue
2. Pending Cue
3. Scene

along with various Text labels I can group in. 

I have experimented with the Fader Object which works but isn't very configurable for these purposes, and as ever I am trying to condense a lot of information onto the monitor.

You could always create a channel object and record that channel's intensity with the active cue number or pending cue number. (Obviously this will not work with cues greater than 100. Also, intensity will be rounded to the nearest tenth.)

I also note the "Cue" object which allows me to specify the target of a cue, but not a list.

Would I be correct in assuming the "Cue" magic sheet objects can only apply to the Master Playback / Single Cue List shows ?

No, you can use the normal list#/cue# syntax for the target, e.g. [2][/][5] for cue 5 on list 2.