by Jim » Thu May 05, 2011 12:35 pm
It is not possible to add new payment methods to ShopSite. There is just too much internal work that has to be done validating data, making the secure connections, updating database fields in a number of locations, displaying the order in the backoffice etc.
An OrderAPI script is executed after ShopSite has finished processing the order. If you were to use the OrderAPi to implement a payment gateway the order would be finalized in ShopSite before the contact to the gateway is initiated, so there would be no way to put that information into the order.
I suggest you add an enhancement request in this section of the forum http://support.shopsite.com/forums/viewforum.php?f=9 to see if the feature could be implemented in a future version of ShopSite.