You can ignore the settings on the Amigo control panel. Those are for folks using their computer at home without eq, mixers, effects, etc.. The settings do the same things we do with our mixer and by using various effects. Just leave things pretty much flat as far as eq goes and do your adjusting on your board.
As far as the sound level, with any device, setting it to 100% is maxing it out - by definition. If you can (roughly) set your levels at each point to between 80% and 90%, as it goes to your board, you’ll have plenty of signal and can use the gain on that channel to adjust according to what you need. This will vary with each artist and equipment set, and room, so you’ll have to fiddle a little to get things just right.
Ted