[carpeperdiem]

You will need to get the variables brought in by products.php

Try this (untested, but it should work):

in products.php

BEFORE

if (!empty($active_modules["Subscriptions"])) {
    include $xcart_dir."/modules/Subscriptions/subscription.php";
}

INSERT

if(!empty($active_modules["Extra_Fields"])) {
		$extra_fields_provider=$product_info["provider"];
		include $xcart_dir."/modules/Extra_Fields/extra_fields.php";
	}

That should enable the extra field variables to be available to the product list (products.php).

ONLY work on backups.