Hi all,
not only concerning the cache challenge I recommend using Firefox with the "Web Developer" extension when you work on themes. If you did not yet install Firefox on your computer try it, the advantages for your theme works are huge. For example using the "Web Developer" extension you can enter CSS properties directly for the open page via the menu "CSS/Edit CSS" and immediately see the page change. Make your theme work with Firefox and if you have everything working as you want, look at MSIE and work on to make your CSS also work in MSIE.
Working with MSIE I sometimes have to repeat the page refresh for 3 to 4 times until I see some changes - and if nothing changes you never can be sure why.
Urs