Hello;
I have this working, but I am curious why it works and why it is needed.
I have an epub2 I made, and works fine in all the apps/devices I have so far tried.
But Apple Books gave me some fits; just a few!

- If I dragged the book to (Apple) Books on my Mac it worked.
- If I synced my iPhone and iPad with that same Mac it worked.
- If I emailed it to either device the formatting fell to pieces in the Books app and all svg wrapped images failed to load.
But...
- If I exported it from Books on my Mac and emailed the resulting ePub it worked in the Books app as expected.
That was a desperation move since emailing it worked for all other apps. So I used Calibre to explore what difference was. Lo and behold I found this:
- iTunesMetadata.plist
- iTunesMetadata-original.plist
Neither file seems to have any rending instructions in it. Indeed, the seem to contain hashes of some sort and a bit of meta-data. But without them the epubs lose all formatting except the base font -- they look a mess.
Can anyone explain to me why?


Does it have anything to do with com.apple.ibooks.display-options.xml being in place?
All in all, it's easy enough to fix, but it is really annoying and a bit obscure. So, any insight would be appreciated.
TIA;
Ken