Thank you, Kovid.
I've never used Calibre's editing features, so forgive me for flying by the seat of my pants. I let Calibre run a check of the book, and took a screenshot of the results
:
http://i.imgur.com/MRMALb8.png (If pic loads small, click it to enlarge.)
I realize that eBook pages don't actually "duplicate." I should have said that clicking to the next page reloads the current page, sometimes slightly repositioned on the screen. Glancing quickly over this screenshot, do you see any culprits?
At this point, I'm merely curious, so no need to go into detail! I'll live with the book as it is, since my creaky old brain isn't up to editing.
Again, my thanks.
P.S. On the off-chance that the first download was corrupt, I downloaded the book from Amazon a second time. No difference.