Sorry the page timed out before I could send, my full reply was:
Looping does not work with Recorded Slideshows, there are three workarounds I use depending on the situation:
1
Do not use recorded slideshow, (clear the recording in Play > Clear Recording) and set the slides to transition at the required time using Delay:
Select the first slide in the Navigator, go to Inspector > Animate, select a transition effect if needed,
in the Start Transition dropdown box; select Automatically
- in the delay entry box enter a value in seconds for the amount of time the slide should display
- repeat for the other slides
- set the presentation to loop in Inspector > Document > Document and select Loop Slideshow in the option box
2
In Keynote, select Loop (Inspector > Document > Document > Loop Slideshow) and record the slideshow advancing through the slides until the last slide when it will loop back to the start, you can continue advancing through the slides again for a second pass, you can do this as many times as needed to obtain the required duration.
3
Create a Recorded Slideshow then export to Movie (File > Export > Movie)
Open the movie file in Quicktime Player and set it to loop (View > Loop) it will loop continuously until closed.