Upgrade PHP Image-Gallery Software

I need an experienced php-programmer to add a number of features and fix a number of bugs in the php-based image-gallery software called phpgraphy. (See phpgraphy [login to view URL]) I've included a 6-page document detailing the bugs and features, please look it over. In summary, the main new features are: -New sort and display options -Allow users download galleries as a zip-file from outside of the folder -Allow users to view newest images/folders, last-commented images, and top-rated images in sub-folders. -Add tagging functionality -Add index-based search functionality, allowing users to search for folders and images, with different sort options And most of the main bug-fixes are about increasing compatability with some member's section software. Because my site is very large and gets a ton of traffic, CPU-efficiency is a must. (Note that my site is an adult site.) Thank you for looking and happy bidding!