Hi Jeff,
You can use a Xone:K1 as a controller for iLive Editor (not GLD), and map the faders to any Input, Mix or DCA. As you said this relies on Editor running on a computer (and the correct Mix being active in Editor) which is not ideal in fixed installs.
With an iLive I would definitely recommend a PL remote controller or instead: PL6 or PL10 if you need multiple faders / knobs or a simple PL4 for in-room level control / source selection.
GLD Editor doesn’t support MIDI control.
MIDI control of Editor is not to be confused with the iLive / GLD MIDI and TCP protocols, which connect to the mixer directly and don’t have anything to do with Editor. You can use these protocols to program third party controllers such as Crestron or AMX (with some luck you might be able to program a generic MIDI controller like the BCF2000 to send / receive the required NRPN messages but I haven’t tried this).
Hope this helps.