Creating Infusionsoft Payment Gateway For Pro Sites Plugin

We are trying to create a new gateway for Pro Sites and Infusionsoft and this will connect
with the Infusionsoft ecommerce module. We created one in past versions of the plugin and it was successful and easy to do, however things with 3.5+ versions has changed.

I have finished creating the class for Infusionsoft payment gateway and I have registered the gateway by writing this function in PHP:

psts_register_gateway( 'ProSites_Gateway_Infusionsoft', __( 'Infusionsoft',
'psts' ), __( 'Use your Infusionsoft Merchant Account to process payments
in Pro Sites', 'psts' ) );

Upon closer look into the new version of Pro Sites, I have found out that I
have to add the tabbing interface myself so I added this additional code:

https://gist.github.com/anonymous/6cb8ecfc6ba3d1d8f5d1

It added the gateway tab properly, but it won't render the settings page. I
discovered that I have to create a separate function for rendering the tab.
But upon checking the codes in Pro Sites, I can see this is not possible to
do because the lines 78 to 83 of /lib/ProSites/Tabs.php (version 3.5.1.4)
is currently commented out. So there is no way to add my own rendering
function for the tab. Ideally, I wanted to make it work with a global
function (as opposed to a class function).

Can you please provide details on how to setup the payment gateway based on our problems listed above. We had this working in the older versions of the plugin and need to upgrade asap to 3.5+ but can't until we get our gateway working again.

Thanks.