I've confirmed that the problem is with the reader--I suspect it is a broken file permissions problem that fix_permissions is designed to fix (
http://wiki.cyanogenmod.com/wiki/Fix_permissions; https://www.mobileread.com/forums/sho...d.php?t=164020). Trouble is I don't know enough about TE, Busybox, or ADB to get the fix_permissions shell working, so I plan to un-root and restore. Much as I like an e-ink mini-tablet-like device, I bought the reader to read, and the Sony Reader app is, afaik, the best reader for the PRS-T1. We'll see what happens.