> I'm trying to figure out how to program/trigger some sound effects to use during the show...
> ...am I essentially limited to 1 instrument/track at a time?
It is possible to have more than 1 track record-enabled at the same time by assigning them different MIDI channels, but if you don't need to record the FX, then you could also patch it in the Environment. You'd cable the device with the pads directly to the Instrument track with the EXS FX (Physical Input Object Pad Device out to EXS FX Channel Strip), and this would then be live regardless of the track selected.