assigning automation to a bus... HOW?

This will get you started - the manual is your friend.

Recording individual fader or knob movements
Recording automation for knobs and faders works in the Track view, the Console view, and Synth
Rack. You can record automation during both playback and recording operations.
To record individual fader or knob movements
1. Do one of the following:
• To write-enable an individual track or bus control, right-click the fader or control you want to
automate and choose Automation Write Enable from the pop-up menu.
• To write-enable individual plug-in parameters, right-click the name of the plug-in in the effects
bin, and choose Write Enable Parameter from the pop-up menu. This opens a dialog that
allows you to choose which parameters to write-enable.
• To write-enable individual synth parameters, right-click the synth’s Automation Write button in
the Synth Rack, and choose Write Enable Parameter from the pop-up menu. This opens a
dialog that allows you to choose which parameters to write-enable.
• To write-enable all parameters in an audio track, bus, synth, or effect, enable the Automation
Write button on the track, bus, Synth Rack strip, or plug-in property page you are recording
automation for. Enabling the Automation Write button on a track or bus also write-enables all
parameters of any effects on the track or bus.
2. Start playback or recording.
3. Move the armed parameter control(s).
4. Stop playback or recording.
After you record the automation data, SONAR draws a graph of it (an envelope) in the Clips pane,
which you can edit with the mouse by adding and dragging nodes (see the rest of this chapter).
Once you record automation data in a track, the widget that you automated displays an indicator to
show that automation has been applied. You can also group controls, so that automating one control
automates all the controls in the group.

hmm. is it possible just to "enable" an automation envelope for a specific parameter, without having to  turn any knobs? In a typical track I can simply middle-click within the track, and choose exactly what kind of envelope I want to create. This doesn't seem possible from a bus, and I don't understand why!

OK, I see now. whew, that's a relief. I was creating envelopes in audio tracks using a method that doesn't work in a bus. I still don't get why a middle-click from a bus doesn't allow me to bring up automation-- eh?

But anyway, so glad to find the answer, thanks!

-Alex

I don't get it, but hey. At least it's not holding me back anymore!

I'm actually a fan of key bindings- does that make me old fashioned? I'd rather enter a shortcut on my keyboard than have to click for ANY menu. I'm still optimistic about X1 and its potential, it hasn't slowed me down as much as others on the forum- in fact, many of my 8.5 sessions have been effortlessly converted to X1... The big benefit is that I can STILL go back to 8.5 if I absolutely need to, though at the expense of the X1-specific data.