If you are using the payment/deposit feature of the ultimate version, the plugin comes with the ability for you to add your own custom payment gateway.
Please note that this is an advanced feature that requires some knowledge of coding and is not something we can normally assist with or offer support for, as we are likely not familiar with the gateway/API you would like to use/implement.
To add a custom gateway, you need to add/create a new plugin. We have built a sample plugin, which you can use as a template.
You’ll find commented notes in the plugin files that provide instructions on how you can modify it to be used for your gateway.