Add New Payment Gateway to WordPress Plugin (Event Espresso)

Hello, Here is our situation:- 1 - We are using the Event Espresso plugin (Basic version - [login to view URL]) for a site to allow the client to sell training courses online. We have setup 2 sample courses on the site: [login to view URL] 2 - Event Espresso supports several payment gateways but not the one we use regularly here in Ireland, [login to view URL] 3 - We need to amend the plugin to allow it to work with the Realex payment gateway using the Realauth Redirect payment method (see the attached PDF for a description of this) 4 - There is a Resource Centre: [login to view URL] 5 - We will supply the Realex Account Name; Account ID and Shared Secret once the job has been awarded along with FTP / CPanel and site login details. 6 - Any changes made to the plugin must be documented so that we can add in the Realex payment customisation the next time we purchase and use Event Espresso