Twenty Ten Gallery Slide Show Not working

If you go to my website, Imagesbyar.com, and go to one of my galleries and select a picture, it used to give you the picture, plus an x to close & go back to the gallery, or an arrow to go to the next picture in the gallery. For some reason it does not do that anymore. Would appreciate any help in restoring this function since now the only way you can get out of that picture screen is to use the back arrow in the browser bar to get back to the gallery. Thanks – ar creevy