I was just trying out MagicDuel for the first time to see what it was like. However, in safari 3 and Firefox 2 i noticed all sorts of issues with regions disappearing behind other regions. So I upgraded to Firefox 3, and found the beginning of game actually moderately playable.
However, when the Ajax overlays are used, like when doing combat and such, the regions behind it pop above it.
As you can see here:
http://rimefire.com/graphics/cssissues.png
It may be some sort of z-index issue or css property or tag that Firefox doesn't like.
BTW I'm using MacOS 10.4, Firefox 3.0, Flash Player 9, Broadband DSL.
On a sidenote, to insure that your site is compatible with most browser, i recommend running it through a html validator such as the following:
http://validator.w3.org/check?uri=http%3A%...ine&group=0
The layout.php page returned 29 errors and 27 warnings.
Anyhow, the game is still alpha so its no big deal, just thought i'd inform you guys of it now.