Sad to say, you went about the process of getting your art out for sale backwards. E-commerce is a different animal from personal websites, and the database-driven programming necessary to run a business site just doesn't fit into the image-structured individual page approach. As Kuroi mentioned above (post 269), you would need to know more about the workings of Zen Cart (or any shopping cart) to fit its pieces into your template structure than to modify ZC to look like your template.
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