I am wanting to pass a Customer ID field from Gravity Forms to Auth.net. I was hoping it would be an option alongside the other 'Authorize.Net Fields Form Fields' on the 'Authorize.Net Transaction Settings' page. I understand that this does not seem to be currently possible. Is there a hook that would make it possible for me to roll my own? I cannot find developer docs for the Auth.net add-on.
I was going to add to this discussion but the topic was closed:
http://www.gravityhelp.com/forums/topic/sending-additional-information-to-authorizenet