It is a 2 step checkout that captures shipping information on the first page (and also validates a zip/city-state match)
Then on the actual checkout page the customer enters their billing info and submits the order.
I only tested functionality on FIrefox which was perfect.
On Internet Explorer (6, 7, 8), the checkout doesn't work at all. The fields are also mis-aligned from their respective input boxes.
This job is simple: help me repair my checkout so that it works across browsers.
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(click the link to get to the download page)