@trekkiegrrrl nearly, but not quite. You get to select one range of frames to be repeated. What I need is the individual parameters' cycle periods, which are all different, need to continue seamlessly, so I can't specify any frame range overall that can be repeated. Each parameter has to have it's own period determined (or specified) and propagated till the last frame in the scene, with proper handling of partial cycles at each end. Thanks for the suggestion, though. Ockham had lots of great stuff. Much of which can be done more elegantly now, with the continual improvements to Poser Python functionality over the years.