I am using El Capitan (with Supplemental Update) and the iTunes version that came with it. I am trying to add an ePub document (that I created) to my iTunes library so I can synch with my iPad to read the file in iBooks on my iPad. However, I cannot either drag the file to "Books" in iTunes nor use the ADD TO LIBRARY command. Neither works. Nothing happens. Prior to El Capitan it was a simple process to do this. Can anyone else confirm that this does not work in El Capitan/iTunes or suggest a work around? Thanks.