I started using the Show/Hide Button and Forms function in InDesign CS6 and have had some peculiar things happen. I was mocking up some samples and on the swf version if you hover over the left side of the blue rectangle all is fine but if you move to the right side of the blue rectangle the image starts to flicker. When you hover over the red rectangle the pop-up image just flickers constantly. I guess there must be some issue with having the button for a revealed image under some portion of the revealed image. See: http://www.idugsf.com/_a/FI_BookSamples.html .
The problem went away when the button and the revealed image did not overlap.
This problem didn't occur with another file I had originally created in CS5.