on the checkout pages, there will be code similar to this near the top:
<?php
//WA eCart Include
require_once("WA_eCart/yourCartName_PHP.php");
?><?php
$yourCartName->GetContent();
?>
where yourCartName is the name of your eCart object.
on the pages that do connect to the gateway, change that code to:
<?php
//WA eCart Include
require_once("WA_eCart/yourCartName_PHP.php");
?><?php
$yourCartName->GetContent();
?>
<?php if($eCart1->GrandTotal() == "0") header("Location: noGatewayCheckout.php"); ?>
on the pages that do not connect to the gateway use this code:
<?php
//WA eCart Include
require_once("WA_eCart/yourCartName_PHP.php");
?><?php
$yourCartName->GetContent();
?>
<?php if($eCart1->GrandTotal() > "0") header("Location: gatewayCheckout.php"); ?>