Shopping cart

Hi I have recently added Zingiri as my shopping cart within WP but having some problems with it. It seems you cannot order products or Catergories in the side bar or turn off both stock tracking and the out of stock warning. I make things to order so want to be able to turn them both off. Also have a problem with the style sheets the WP style sheet overides the Zingiri one so that you have to have the same buttons along the top of your page as in the shopping cart buttons. This simply does not look good.

My question is would the WP shopping cart solve these problems? If so what are the weaknesses of WP shopping cart compared to Zingiri?