I need the following hack to the VM: actually, if I want to trace a stock quantity for a product, VM can do it, but if the product is composite, VM does not do it: What I mean for composite product? example: standard product "1 banana" in this case I insert in the Vm backend the number of bananas I have in stock so when someone orders a banana VM take it directly from the stock. Composite product: 1 basket of bananas, apples and crawnberries. How can you see this product is a basket and is with it's own sku, but it is an aggregation of 3 different products I have in stock: 1 banana, 1 apple and 1 crawnberry. Obviously I have not in my stock ready baskets, I have only bananas, apples and crawnberries, if someone orders a basket, I need to take it's components from the stock and compose the basket. What I want is this: on the product backend management must be a check that asks me if this product is a single or composite. if it is composite it needs to ask me on what products Vm must take it's components, after, it needs to ask me in what quantity (grams or pieces), then when someone buys this composite product VM goes to subtract each of it's components from the "pure" products stocks. In this way I can have a real control of my stock.