Torgos, I think I'm probably going to go the route that you took and create something custom for my needs. I was trying to do something general in order to make a contrib module, but I think the uses for something like this are going to be fairly unique. My main problem in trying to create a generic mapping of any content type to any product type was pulling out the meta data in a way which gave me all the important fields that you'd want to map (like attributes) while leaving out all the fields that you wouldn't want to map (like nid). The goal here basically being on the fly product creation and purchasing. I got the sense that Steve was doing something more along the lines of adding an existing product to a cart from non-product nodes.