Custom PHP Shopping Cart with MySQL needs more functionality

So I need this done immediately... (don't we all). OK, the shopping cart came from a package... please see the following link for more info regarding the software the shopping cart/eCommerce was customized upon. [login to view URL] Anyways... that's not my website... but I'm told that is the code that was used to create it. Moving on - I need to add new products. I click on the button 'Add product' and it takes me to the input screen with all the fields. I fill all of them out and hit submit - and then nothing happens... no trying to load anything... it acts like a button without any code associated with it. I'm well-versed in html/css... but not so good at PHP and the associated MySQL. This shouldn't be too hard as I've given you the link to the original source code... something is simply broken or missing. MUST BE AWESOME AT MYSQL AND PHP! Please note... I already do have other, more time-intensive projects in mind for this site... but this is one that I need done NOW. Winning bidder must be able to fix this problem within 24-48 hours. Thank You!