How the shipping is managed in this Marketplace Extension?
Shipping charges will be directly transfered to admin's account. Only those shipping methods will be applicable for the customer to select while ordering which are enabled by admin. If you want the vendor to manage to ship then you need to purchase Vendor Multi shipping Add-on and any respective Vendor Shipping methods. From here you can purchase Vendor shipping Methods: http://cedcommerce.com/magento-extensions/shipping-methods