How to time a Keynote Presentation to a music soundtrack

I often do weddings and funerals, and as part of the wedding or funeral people like a Keynote slideshow with 10-20 photos set to some background music. ┬áThe problem is there may be other slides that need to come before or after it without background music.┬áThe easiest way to achieve this is to make a ‘movie’ of the slides (with a soundtrack) and then re-import this movie into a Keynote as a single slide. Here’s how to export a Keynote slideshow with a soundtrack.