[MarketPress eCommerce] Product Category Shortcode

Using the E-commerce Add Shortcode button found above the standard page editor I was surprised to find that displaying products from a specific category was not an option. I tried to use the display related products shortcode and unfortunately that shortcode is not working at the moment.
What I am trying to achieve is to provide a more detailed description of a product category that appears above the list of products in that category. Maybe this is a feature that already exists and I just haven't figured out how to do it.

So, if you can either let me know how to do it with the current set of features or provide a new shortcode that will allow me to achieve this result it would be fantastic!
Thanks,
Pat