CSS Fly Out sidebox or at least display category link as block on mouseover ?

[styrax]

I recently downloaded the CSS Fly out categories sidebox contribution.

I can get the fly-out subcategories working in I.E. without too much trouble by manipulating the width & margin definitions within the new sidebox CSS stylesheet to match the column width definitions within my Admin Layout Settings. However, the sideboxes then dont display properly within Firefox.
Am I missing something obvious?

Alternatively, all I really wanted to achieve was to get my sidebox categories to dipslay as a block on mouse-over but I can't find the class identifier to differentiate sidebox links from other links on the pages.
Can anyone point me in the right direction, please.

Phil