The Problem
I need to add a button to "continue shopping" in the checkout process. The problem is, once the user clicks checkout in the shopping cart and the browser loads the checkout page the shopping cart is now empty, so if the user goes back to the product list page they cannot add to their current shopping cart. Also, because at this point they are no longer on the checkout process the order is inaccessible as well. They would have to recreate their previous shopping cart selection.

What I would like...
I would like for the shopping cart to remain until the checkout process is completed, and to be able to add a button next to the cancel and continue buttons in the checkout page.

Is this possible?