I'd like to have a character move a limb to three positions in a sequence-- let's say waist high at 0, head high at 30 and back to waist hight at 60. Perhaps I add a wave at 45. Poser 11 makes me crazy because it adds sine curves between the key frames, especially in complex sequences, so the figure is flailing or bending in ways I never intended. How do I tell Poser not to 'invent' curves above or below the keyframe I indicated?

Spline break between each action.

Is the spline break enacted with the small symbols at the lower left of the graph? I’ve tried that but it hasn’t worked. Maybe time to RTFM.

If you want a nice smooth movement then you need to put another Key one frame after your first key. So you put in 1(0),30 and 60 then you need to copy each of those keys adn paste them 1 frame up at 2, 31 and 61 (or 59) if you don't want to add to add extra frames. The other way is to turn all frames to Linear and you won't have any overshoot. I have 4 or 5 bug reports in about Poser's Spline curve and how it fails and what should be done to fix it.