Authorized.net getaway integration in billing system

we have a personal customer billing system written php (wiht mysql DB) that works with paypal, worldpay and 2chechout getaways. We like to add the [login to view URL] getaway to this script. The integration must be full working wiht our script (as well as process recurring payments that already works with other payment getaways) Additionally we like to made some small changes as: - add 3 more currency symbols - change 1 table bachground color - add 2 more fields to user registration form