DPS is not supported under CS5.5 or CS5.
But in this tutorial you can create scrollable object using Indesign CS5.5 and Overlay Creator (I was able to do that, although I don't have the preview button):How to Create Scrolling Content in your Digital Publication using InDesign CS5.5 | Adobe Creative Cloud TV: Designers | … where do I go from there?
How do I export it?
As you can see I have a Folio Builder Window, but for some reason I can't update it:
As I said, DPS is not supported any longer under CS5 or CS5.5.
Thanks : (