I'm having some problems wrapping my head around parallax / fullscreen too. It doesn't work the way I expect it to <img src="smileys/smiley1.gif" border="0" align="middle"> and I think it's buggy.
Here's what I mean: CAPX.
It contains 2 layers, one of which has parallax 0,0.
Switch the project property "Fullscreen in browser" between "Off" and "Scale mode", and run the project.
When "Off" it looks as I expect it to. Buttons on the zero-parallax layer show in the four corners.
When "Scale mode", it looks very weird.
Can you explain how this works, why is it like this?
What I'm trying to achieve is a "fixed" (HUD / GUI) layer staying in place, and a moving layer moving around. I need this to work on "Scale mode" fullscreen.
Thanks in advance.