Marketpress Shopping Cart Issues

I need some assistance with the Marketpress shopping cart.

One of my merchants in my multi-site network is having trouble with their checkout process.
#1. They have E-books for sale, but when you add it to the cart to purchase in Internet Explorer the shopping cart shows "0" items in cart (refer to screenshot).
How can I get the # of items that's in the shopping cart to display in the upper left-hand corner?
#2. When you go to checkout to purchase the download, I get an XML statement error under the "Choose a Shipping Method" section. It says, "The XML document is well formed but the document is not valid".
(refer to screenshot).
#3. How can I remove the "Choose a Shipping Method" option that displays in Checkout for all Product Downloads? I just want customers to be able to pay for the downloads and receive the file.

Please Help,