Is there a way to add the ability to edit or add a shipping address in the multishipping checkout process similar to how many onepage checkout extensions do it (example: http://www.magentocommerce.com/magen...-checkout.html). I have placed some form elements in the correct pages, but I'm not sure how best to proceed. Any help would be greatly appreciated! Screenshots included;

Multishipping Overview Page

Multishipping Addresses Page