Does the plugin support custom ticket fields?

I’m using this plugin to connect my Gravity Form to a Zendesk account. I have the account connected, and a feed setup for my form. However, when I get to the step of mapping the form fields to Zendesk, the only Zendesk fields available for mapping are the standard fields. I’ve added several custom ticket fields in my Zendesk account, and I need to be able to map those from my Gravity Form as well. Any advice is appreciated!