Hi, this is great! well done!
I notice two things:
1. at the bottom of the product screen in the admin it shows a section for Joomla Custom Fields but it's blank. I am assuming you are working on this but wanted to alert you in case it was a bug.
2. when you view a list of products you cannot view ALL. So if I have a root category of Products and then subcategories for each type of product, I can only see by category not root.
3. It would be nice if I could grid or list the product list view... just a thought.