I did more testing and could reproduce this bug ALSO on Windows (Firefox 3.0.11 / Flash 10,0,2,54).
Try force-reloading the page a few times.
[INFO] time 07:56:17.816 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'screen', target Z index is 0, numChildreb 0
[INFO] time 07:56:17.827 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'null', target Z index is 100, numChildreb 1
[INFO] time 07:56:17.837 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'gallery', target Z index is 100, numChildreb 1
[INFO] time 07:56:17.841 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'filmDeControls', target Z index is 3, numChildreb 2
[INFO] time 07:56:17.847 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'play', target Z index is 100, numChildreb 3
[INFO] time 07:56:17.850 :: org.flowplayer.view::Panel : updating Z index of [DisplayPropertiesImpl] 'fskInfo', target Z index is 100, numChildreb 4
Update:
Problem exists also in IE 8 w/ 10,0,22,87 where the zIndex seems to be randomly changing.
Try the demo there.
The plugin stack should be
4 Rating (Text w/ green icon)
3 Gallery (mouse over player to show gallery control)
2 Custom control bar (mouse over player to show)
1 (video)
0 Background