I'll check later, but just off the top of my head... I think you can send an input to a monitor without sending it to the mains in 2 ways. Option 1 - Select the click track channel and turn off "stereo bus" to turn off the send to the mains. Then you can unmute the channel in the monitors and it will never go to the main. Option 2 - Just keep the fader on the click track channel down in the mains (with "sends on fader" off) You have to unmute the channel because it's a "master" mute for that channel, but as long as you keep the fader down it won't come through the mains and you can send it to other monitors using "sends on fader"

Hey man, you want to change the main outputs to outputs 15/16 to get control of the volume by using the main (L/R) fader far right on the board. Hope that helps.