I use the "stored in a cookie" version of the cart. I'd like users to be able to change a value of an item after it has been added to cart (a bit like users can change the quantity from the "basket" page after an item has been added).
In my case the cart has an extra field for a "packaging option" - in the basket page I want the user to be able to change the packaging option via a SELECT list (there would be a select list per line in the basket) and that change to update the basket.
Can this be done? - how can I target the correct column and item number from the cookie and how can I change the value currently stored in the cookie with the new value for that item?