Major Description
If in the ProductStore, the explodeOrderItems flag is set to Y, during order creation the shopping cart items are exploded: the process is done cloning the original order items (mostly using the the ShoppingCartItem costructor that takes as input a ShoppingCartItem object).
The problem is that the CartShipInfo objects are not properly cloned when shopping cart items are exploded.
So, when a cart item is cloned, ship info is not present in the cloned items (and reservation is not performed etc...).
Not sure it is related but also the sales tax adjustements are not applied to the cloned cart items.