The output of each fader strip must be assigned to a Program output.
Press one of the PGM keys on the fader strip; it will illuminate to indicate that it has been assigned.
Press the On key at the bottom of the fader strip and move the fader up.
Your meters should be active as shown below.
To hear audio, make sure you have selected the same Program assigned above as a source to your CR Headphones or Speakers using the controls on your Monitor module, and that the volume is set to an appropriate level.