Build a Widget for a Mac based program called Everweb

I built a site for a client using a program called Everweb. My client wants to have a section added that has countertops that when clicked on a certain type of stone, the countertop will change. This is the type of effect he wants. Play with it and see. [login to view URL] The current site I made and that he is using is [login to view URL] So I need to have a widget built so I can drop it into my current program and then insert the stones and countertops. Can you do it? How long will it take you to complete the task?