I am doing animations involving going from screenshot to screenshot in individual scenes. This is so we can "simulate" a software task for a learning environment. It involves mostly, besides the screenshots of the software at various points, textboxes with instructions for the student and hotspots to move to next scene, etc. Mostly really really simple.

We are making these into widgets to run on iPads in iBooks. Once in a while, one of these animations seems to get sort of jumpy or choppy - between scenes (and screenshot images). The browser (well, ibooks widget thingie) goes blank before you see the next screenshot. What could be causing this? Is there a preloading that happens with Sencha outputs, and if not would a preloading of the images help? Am I missing something in the timeline (a keyframe, etc) that I should make sure is there? Just trying to troubleshoot this.