Another set of code missing in the update section of the observer class (includes/classes/observers/class.products_with_attributes_stock.php) needed to fully support ZC 1.5.1 without modifying other files. (in the past includes/modules/pages/shopping_cart/header_php.php had been modified to support the plugin. Apparently the modifications were removed without enabling the method for ZC 1.5.1 that is operational in ZC 1.5.3 and above.)
Code:
if ($notifier == 'NOTIFY_HEADER_END_SHOPPING_CART') {
$this->updateNotifyHeaderEndShoppingCart($callingClass, $notifier, $paramsArray);
} //endif NOTIFY_HEADER_END_SHOPPING_CART
Will be uploading the modification to GitHub as soon as I can.
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