Hi! I want to advice you one more extension you can use for adjusting your shopping cart.
AJAX Shopping Cart Extension is a nice way for adding ajax shopping cart to online stores. The extension adds products to cart with no additional useless page reloads, so customers can rapidly add items to cart without interrupting the shopping process.
The AJAX Shopping Cart Module supports configurable products and custom options.
It allows to choose time period for cart overview display. Also it offers flexible shopping cart dialog window, for which you can choose block position (left, top left, right, top right, center, top), whether display product info or not, show the number of products in cart or not, show the subtotal or not.
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