And now, to ask for help with the problem I just turned up.
As described in the post above, I got automatically upgraded to 5.3.3, and lost my screensaver (I only have one). After getting impatient, downgrading back to 5.3.1, re-jailbreaking, etc, etc, etc, I got my screensaver working again.
However, it only works once. After that, the screen just locks on the page I'm reading. I can get it back for one iteration by touching a reboot file in the linkss folder.
Doing some reading through the thread, it appears I may have a bad png? It's odd, because it's unchanged from the one that worked perfectly before the upgrade to 5.3.3.
Help? I'd be happy to post the png file I'm using.