Magento, SCP, Firefox and Chrome issues

Hi there! I am having some issues with my e-shop (Magento 1.5.1.0) and Simple Configurable Products (SCP), a third party extension. My first issue has to do with Firefox and SCP. When I use Firefox the price ranges in Configurable Product Option dropdowns are not shown and the price after every selection goes to “0.00”. The “buy” button doesn’t seem to work either. Everything seems to work just fine with IE, Opera, and Safari and Chrome though. My second issue has to do with the product picture that gets dynamically updated when all configurable options are selected. The updated image is displayed full sized and covers up the product’s options. This only happens with Chrome. I need someone to fix those 2 problems.