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Yes! I got it working, thanks. I moved the animation frame advance cursor back to the start, and Merge, then applied a Pose Preset I had of it and now it works. 

I also moved the End marker up much closer to the beginning.

But now the next question: Is there a way to limit the range of movement in a previously made by someone else animation? To me her butt bounces a little too high. Is there a way to restrict the range of upward movement there? 

click on that frame where the butt animation goes to high and then modify the dials that make the animation.