[Karellen]

I am wondering if iBooks requires some unique code in epubs to render them.

I've sideloaded a book series onto my iphone. Some of the epubs are rendered blank and I can only see the cover image. Other ebooks are perfectly fine. Out of 10 books, only 4 are rendered correctly.

CheckBook and EpubCheck are both clear. Both working and non-working epubs are structured and coded exactly the same. I can't see a single difference between them (obviously apart from the story text). There are no colours or backgrounds in the css to hide the text. I am at a loss as I can't figure out why they won't display.

Has anybody experienced this and know the cause?

I guess some will tell me to use another app, but that does not help as I would like to figure out where and why there is an error.