It appears the problem might be here in payment.php
if (defined('MODULE_PAYMENT_INSTALLED') && tep_not_null(MODULE_PAYMENT_INSTALLED) {
Point works with it this way, but CCGV does not. There was a change left out of the CCGV instructions -
// Start - CREDIT CLASS Gift Voucher Contribution
if (defined('MODULE_PAYMENT_INSTALLED') && tep_not_null(MODULE_PAYMENT_INSTALLED) && !$module == 'credit_covers') {
// End - CREDIT CLASS Gift Voucher Contribution
After this change, the CCGV works, but points has the error message.