this is a great plugin, but I have founded a bug with cart calculation.
1. Add one item to cart, that price is $10.
2. Then add same one item from Photos page(not cart page).
3. View cart page. The Totale Amount is expected to be $20, but will be displayed $30.
I suppose, the cart seems to be calculated based on the total number of the item, rather than the quantity that has been added.