I tried your file in IdevioMaps (http://bi.idevio.com). There it can be displayed but it is not really practically useful. The sense map has a limit of 1000 objects I think. The main problem is that there are too many (more than 7000) detailed areas to be displayed at the same time. The usual solution in these cases is to do a drill down hierarchy with IdevioMaps. You then would need to have some more information that you can group your areas with, such as county. Then you could make a drill-down hierarchy and first display all counties. When one county is selected you would display only the areas in that.