This does not work. I have audio files which it insists I have added outside widgets, which I have absolutely not done in IBook Author.
The only way I could get the updated iBook into my package was by creating a whole new package and reentering all the metadata information. It did seem to take the sample which also had some of the same audio and video files created in the same manner. Very frustrating.
MacBook, Mac OS X (10.5.6), iPhone