customize a magento extention

I use this free extention on my website for wholesale registered customers so they can view the quantity and place an order from one page. due to having a lot of skus the page load is slow and some customers asked to add filter to the page, since we use configurable products by size we would like the size to be the filter option. check my website [login to view URL] you must register and be approved in order to see the quick order page, you can navigate back to the retail website here [login to view URL] you can see that there is layered navigation on the left bar which is what we would like to achieve on the quick order page. I have customised the extension to display the stock count next to each product so i can guide you if you need any help. it is just that i have reached my PHP limit so time to hire an expert :)