Hi Luis.
The groups on iLive are very similar to those on the ML4000. There are two types of group – Audio groups and DCA groups. Audio groups are configured from the 32 mix buses in the same way you configure the auxes. Yes, they run like an aux bus but they do not have channel sends. You assign channels to route to the group. The group can then be used to process the routed signals, for example one compressor on a group of backing vocals, or a graphic EQ on a group of stage microphones before you route them back to the main mix. You can also use these to group different signals to feed the matrix, for example to balance more vocals than orchestra to a delay fill in a theatre, or add more drums to a stereo live recording created from the LR mix. Another application is to combine signals to feed a multitrack recording where you have more channels to record than you have tracks.

DCA groups are the digital equivalent of the VCA groups you had on the ML4000. They do not pass or process audio and are simply remote masters to control the levels of channels assigned to them. If you are mixing a band you could assign a few to give you master level adjustment and mute control, for example DRUMS, GTRS, VOX, FX. Your starting point is to set the DCA masters to ‘0’ (normal level).

Both the audio and DCA groups are assigned in the same way. Press the master MIX key, hold down ASSIGN and press the MIX keys of the channels you want to assign. You can find out more about the differences between and application of groups by downloading the ‘Mixing Live with VCAs’ document we wrote for the ML consoles. https://www.glseries.com/UK/ViewProductDownloads.asp?search=Mixing%20Live%20With%20VCAs
Let me know if you want more on this.
Regards,
Carey