All active development on zoom.it stopped when Microsoft Live Labs was disbanded three years ago. Sorry, but what you see is what you get. We're thankful to the support from the Bing team that operates (and pays for) the zoom.it site.
You might want to take a look at the Seadragon control in ASP.NET Ajax Toolkit. (http://www.asp.net/ajaxlibrary/act_Se...) You can build your own zoom.it-like experience using this open source control based on the same technology.