:smartalec: alright it's done and for anyone else that may need to do it this is
In order for you to use eProcessingNetwork with Zen Cart you will need to use our Authorize.Net TM Emulation. All you need to do is replace the Authnet file in the Zen Cart's catalog/includes/modules/payment section with the one I have attached to this email.
Then you will need to login to the Merchant Support Center, https://www.eprocessingnetwork.com/MSCLogin.html choose Processing Controls from the drop down menu, and scroll to the Advanced section. Here you will check the box to turn on the RestrictKey. Then click the button Save RestrictKey and Policy.
Once you have replaced the file and turned on the RestrictKey you will then Login to the Admin section of the Zen Cart and edit the Authorize.Net TM payment module. Use the ePN account number for the Login ID and then but the RestrictKey in for the TransactionKey. Make sure that your cart is set to Production, test mode does not work with eProcessingNetwork and this type of setup.