Photo sequence slideshow, how do I make it autoplay?

I've used the "Presenation" tool in Express to create a simple photo slideshow. It is 5 images, one on each page, with dissolve transitions... how do I export it so it just plays automatically as a sequence? I don't want to have people click through the pages, I just want it to play through automatically.

I can do this hard way in Phtoshop by creating an animated gif, with tweens. But I thought Express was going to make it real simple and save me from manual labor in PS.

Please advise.