Automating Guitar Rig 4 - dumb question

Please forgive the dumb question (I did read through the Guitar Rig manual and the X1 Help, and I still couldn't figure it out) - I'm using Guitar Rig 4, the version that came with X1 Producer and updated to the current NI release. I want to increment the preset at a certain measure in the song, and cannot figure out how to automate that. I recorded a MIDI track, which I send to one track of the Garritan JABB ARIA player. I inserted Guitar Rig as an effect in that track. I created a tag list in Guitar Rig, so incrementing the preset will take me directly to the next sound effect I want. From the Guitar Rig screen, many of the parameter controls display their MIDI CC# when right-clicked. The button to increment preset does not do so. I tried taking an automation snapshot of the ARIA track, but I only see the Automate Snapshot option appearing when I right-click the track parameters such as volume, pan, etc., not when I right click on Guitar Rig. I'm sure there's something simple I'm missing here. I appreciate any help you can give me.

 Hats off to you, Ethereal Entity. If this information was in the Guitar Rig manual, it was impossible to find. Your instructions are great and matched the screen display perfectly.