Sweet supports "live" shipping estimates from UPS and Fedex. If you are using shipping methods that rely on UPS and Fedex for cost estimates, then the order page changes a bit as described below.
As an admin user, if you are on an order page with items in the cart and you add or remove items to the order, a link would appear below the shipping method with the label “Recalculate shipping charge” and the “Submit / Approve” button would be disabled.
A confirmation dialog saying “Shipping has not been updated. Are you sure you want to approve this order?” would come up if you try to approve order when shipping recalculation is needed.
You should still be able to manually edit the shipping charge and “Apply”,which overrides the calculated shipping charge.