And speaking of ADE font rendering, the only reason I even tried the newer versions is that a couple of months ago, my v2 installation began rendering ALL fonts very poorly, even its own default fonts. Very spotty and ragged, like a very poor scan of a faded old book. Un- and re-installing did not help. The new versions do the same. I would assume it was a computer video-chip problem, except all other software displays fonts as normal.
I shall have to visit the support forums for my laptop, I guess.
@Doitsu, thank you for the epub3 tips. I haven't dipped my toes in that cold water yet, maybe it is time to start learning to swim.