Cursor Scrubbing/Advancing, like "Two Birds of a Responsive Feather"

Hi!

I would like to know how does one use the cursor to scrub/advance the timeline, just like in "Two Birds of a Responsive Feather" found under Adobe Edge Animate's Showcase Page, found here:

http://html.adobe.com/edge/animate/showcase/birds/

Notice that the clouds move with the cursor and that the birds are unaffected, that is the effect I would like to achieve.

I am fairly new at Edge Animate and I am sure this is just a simple fix.

Thanks,