Oh, interesting. I responded to your other thread, but the video at least tells me what you're trying to do.
I have seen someone keyframe the feet cycles to match a Walk behavior that just did the movement and bounce.
BTW, that "when triggered" behavior is correct. Imagine you wanted to shoot lightning out of someone's eyes. You don't want the lightning always visible. That said, for your case, you do want some legs to be visible. The workaround would be to use a swap set. The default trigger in the swapset could be the artwork, and the other trigger could be the Cycle Layers animation(s) you want triggered.
All that said, I think the best way for you to get what you want is to use Mode: Position-based, then keyframe the Position parameter. Now your timeline should have the body moving and bouncing up and down. Then you can manually edit the triggers in the timeline to syncronize with your walk. Once you've gotten a few in sync, you can copy and paste them down the timeline.
You'll probably want to use that Swap Set technique I was referring to earlier to make sure the body doesn't disappear.