Mapping auto-gain?

There's no input MIDI mapping control for the auto-gain because it's not intended as a performance function. That, as you say, is the kind of thing you set before the gig. If you're live AT a gig, you would simply adjust the gains on the mixer channel to adjust it, or click over to the grid adjust panel and dial it over to where you need it.

I understand the ease of using a hardware knob to make this change, but I, for one, wouldn't want to have any accidental changes made because I hit the wrong knob while the track was loaded.

That's the kind of thing you set once. Did you mean the GAIN level?

Nope - I definitely mean auto-gain. Track analysis doesn't always get the auto gain correct, especially on older tracks. I want to be able to tweak the auto-gain setting the first time I play a track so the next time it's played it'll be set correctly. I know I can do it by tweaking the auto-gain setting on the computer, but in a live setting I'd much rather be able to do it using hardware rather than by using the mouse. I know I could probably do this at home before a gig, but playing weddings/parties is very request driven and being able to change this easily while at a gig would make life easier.

The channel gain controls are ok for vinyl where you can't save the levels, but for playing from a computer they shouldn't really need to change once the auto-gain is correctly set for a track.

Mike