I've customized my cart page, and I've added a feature to get the shipping based on the zip code and weight of the products using our Freight System.
The results return fine, but when clicking on checkout, the shipping cost is not carried over.
I have an event on the checkout page to recalculate the shipping based on the hidden field h:shipping which is the one I'm setting on the form.
It works fine when I go straight to the checkout page, but it's not carried over in this scenario.
Even if I update the cart on the cart page using the update button that fires UpdateCart() method, the hidden field is not saved.
Is there a way to make sure that this custom field is persisted on the cart so I can use it on the checkout page?