css javascript trick

there is a web site [login to view URL] and what we need is to place over all site a new div with a transparent PNG div. what we want is 1. the transparent div to be adjustabe to screen resolution 2. all elements bellow this div to work as they work with out I mean slideshows and links. As you can see at the posted link there is a slideshow and some links bellow the slide show after the placement of that dive we want those elements to continue to work. 3. the solution should work to all browsers (chrome, safari, IE7 and above, mozilla)