Extending Marketpress using action hooks

I am trying to extend marketpress functionality but not able to do so unless changing the core.

I want to be able to store the order ID generated after the payment is processed successfully. In the gateway files or the primary gateway file, i am unable to find any hook that can help me do that. If there is a way, please kindly let me know.

I would really recommend adding hooks (do_action) for most of the major functions in marketpress. Without them its nearly impossible to add anything that's not present by default in MP.