今天我添加产品到购物车,重复添加 出现下面的错误Nominal item can be purchased standalone only. To proceed please remove other items from the quote.只有注释下面几行就ok了 

public function addItem(Mage_Sales_Model_Quote_Item $item)    {        /**         * Temporary workaround for purchase process: it is too dangerous to purchase more than one nominal item         * or a mixture of nominal and non-nominal items, although technically possible.         *         * The problem is that currently it is implemented as sequential submission of nominal items and order, by one click.         * It makes logically impossible to make the process of the purchase failsafe.         * Proper solution is to submit items one by one with customer confirmation each time.         */        if ($item->isNominal() && $this->hasItems() || $this->hasNominalItems()) {     //        Mage::throwException(      //         Mage::helper('sales')->__('Nominal item can be purchased standalone only. To proceed please remove other items from the quote.')        //    );        }
而且返回来的数据 不对,找到checkoutsidebarcontroller.php修改如下
public function sidebarAction(){ $totalQuantity = ceil(Mage::getModel('checkout/cart')->getQuote()->getItemsQty()); echo $totalQuantity.'item -' .Mage::helper('checkout')->formatPrice( Mage::getModel('checkout/cart')->getQuote()->getSubtotal()) . '<div class="actions"> <a href="'. Mage::getBaseUrl('web').'checkout/cart/" rel="nofollow">View Bag</a><span>|</span> <a class="checkout" href='. Mage::getBaseUrl('web').'checkout/onepage/" rel="nofollow">Checkout</a> </div></div> ';}

至于模板和css的修改请参考maradress的文件.