I am getting the endless progress bar in IE8 still, even after applying the aforementioned patches, setting IE8 privacy and content settings to the lowest setting possible, and everything else I can think of. This is screwing me out of sales because people try to buy products for a cost and for free but it won't work so they leave.

If I add a bunch of free items to the cart and go to checkout, it displays fine. If I add any items to the cart that cost money, whether alone or in combination with free items, I get the endless progress bar.

It works fine in Firefox. I have tried everything, and the only way an IE user can buy a product is if I disable the free products module altogether.

You can try it yourself at http://www.designpanoply.com/ Add any products, and the free things are on the freebies page obviously.