iPhoto ’11: The Macintosh iLife Guide to using iPhoto with OS X Lion and iCloud

Purchased Songs and Slide Shows

You can use songs from the iTunes Store for slide show soundtracks. But if you plan to export the slide shows as QuickTime movies, using the technique described on page 133, note that the songs will play only on computers authorized for your iTunes account. The workaround: burn the songs to an audio CD, then re-rip them into iTunes, and use those unprotected versions for your soundtracks.

Note that this limitation applies only to old iTunes purchases that are shackled by digital rights management (DRM) copy protection. These days, virtually all iTunes songs are not DRM-protected, so you can use them in your slide shows without worrying about whether they’ll play on other computers.

But if you have tunes purchased ...