Repetier Host adding Extruders?

[McgLance]

Hi,

The A30t says the supported slicer is Repetier Host, and I loaded the config files... which I had to search for, being that it only give me the option of selecting 1 extruder with cura slicer, how do I add the other 2?
This is really holding up my prints, and need to get sorted so I can start printing..

Thanks.