How EXACTLY did you create this effect?
Create buttons from the three elements involved in the Buttons And Forms window:
1. One button to show the pop up upon clicking. Actions with clicking show the two Buttons 2 and 3 below and to hide itself (because Buttons always are on top):
2. A Button (group consisting of the black full page frame and a information frame), hidden until the first button is clicked (using the eye, crossed eye and the cross icons in that Buttons And Forms window).
3. A closing Button, also hidden, same actions as button 2. Added action is to close 2 and 3 and show 1 again when clicked.
Hope this is clear enough (have to translate the terms from Dutch).
A picture to clear things up further I hope:
The problem is clicking outside Button 3 disables it.
Button 2 (which is the background) hides all three buttons so what you're seeing is exactly what I would expect.
FWIW, I will repost my feelings on doing this with a PDF. This is just not what interactive PDF was intended for and there are far better methods with other formats.
Oh, no actually, there's no action on button 2 (I accidentally added it my mockup, it's not in the original file. Just the 'hidden' tick at the bottom). So clicking should do nothing.
I keep telling my collegues* that PDF is not the best format for a lot of this kind of interaction, because I think very labour intensive and the end results leave a lot to be desired, maybe your article helps me strengthen my argument.
* We even had clients to insist on it, for whatever reason.