I never have problems getting CSS to work in either firefox or MSIE, the trick is making one CSS file that works for BOTH.
For instance, the 'hand' (pointy finger) when you want to do an onClick event, say, on an element that otherwise would yield a text bar or normal pointer. MSIE uses a nonstandard name for it (hand) and firefox uses the CSS2 standard (pointer). However, you can exploit a CSS style interpretation 'bug' in firefox where it'll only recognize the first definition in the style to have the cursor work for both browsers:
.pointerstyle { cursor: pointer; cursor: hand; }
It's crap like that which makes life interesting for people who do dhtml UI work. I just look at it this way: for me, it's all billable hours.
