Working Paypal Module for Prestashop

I just finished adding the Paypal payment option for our e-commerce site that uses Prestashop as the shopping cart application. I'm quite getting more comfortable configuring and editing the source code of Prestashop, but along with those modifications is the failure of the default Paypal payment module that came with the Prestashop code package to fail.

Prestashop: Remove Default Shipping Fee Being Added To Total Price at Shopping Cart

If you've been developing e-commerce websites with Prestashop, one main problem that has not been solved in the latest release (Prestashop 1.1) is that the default shipping is immediately added when checking out at the shopping cart. This poses a problem when there are more than one option for shipping methods, and their prices differ from one another. Here is a very simple hack to prevent the default shipping fee from being added to the total price at the Shopping Cart summary page without the need to modify any code: