Hi folks. Sorry about the delay. For some reason (???) I did not get notifications of your replies to my post here. I just came here today to see what's what...and here you are.
Given that this is my first ebook offering in a reflowable format, I probably don't know enough of the ins and outs of it, mechanically, to anticipate all that can go wrong. That said, it looked perfect in my iBooks app. on Mohave and in the Readium reader in Sigil in Sierra. I thought...okay, it works and looks pretty good. But apparently, it's not that easy.
I'm formatting another ebook/print book right now and will be up against the same issue. I think I'll have to look into this deeper.
What concerns me is when a distributor doesn't contact you to say "Hey, this looks like crap —*what happened?" I mean, it's going to their clients via their distribution network. And all I knew at the time was that it passed through their screening process. So I thought...okay, I'm set.
Nope. I'm not.
Anyway, thanks for your feedback. Much to digest.