<strong>Update (3/Oct/2011): CS5.5 exports links from multiple chapters correctly! </strong>
There was a great discussion about InDesign CS5's links bug this morning on the #eprdctn Tweet chat, hosted by Lindsey Martin (@crych). (Join in by following #eprdctn on TweetChat Wednesday mornings 11am EST.)
Here's the recap:
If you have a multiple document InDesign book with hyperlinks or cross-references that go from earlier chapters to later ones, and export this book to ePub, the links will be malformed, missing the file name portion of the link, and thus will not work.
These failed links generate validation errors from ePubCheck (whose approval is required for acceptance into the iBookstore).
Internal links (within the same document) or links to earlier chapters will continue to work (and are formed correctly, with both file name and fragment identifier).
Links in InDesign books also fail if exported to PDF as Interactive. (Exports to Print PDF work properly as long as Include hyperlinks is checked.)
InDesign CS4 and CS5 do not include the date upon export to ePub, nor have a way to manually enter the date, thus causing validation errors with epubcheck.
This is a major bug and pretty much incapacitates InDesign as a serious ePub generator until it is fixed.
Bug errors have been posted with Adobe, and several InDesign specialists have been notified. Hopefully, Adobe will post a fix soon.