jQuery / Javascript guru needed for quick fix - repost

We need a jQuery wiz for an hour or two to fix our gallery as we wish. We had a previous developer who let us down so need someone to pick up this project. [login to view URL] 1) Make sliders scroll smooth and consistent 2) When you click on a thumbnail and the pop up is open, the right arrow doesn't appear ([login to view URL]). For the first thumbnail the left arrow should be half greyed out and not clickable. 3) The back button should be half greyed out and not visible until you go to the next page. All the pages must be aligned to the PSD. Many more pages to be built if this goes smooth. Needs to be fixed today ASAP.