In a previous post, I provided an example, showing how basically to re-use the Kendo's demo logic with RadMap. It can serve as a pointer to examine how the structure is in RadMap and how iot related to Kendo Map.
Basically, using RadMap, you are using Kendo Map. You do not need to add, reference or download Kendo resources. With adding RadMap, they are loaded automatically. RadMap is just a wrapper of the Kendo Map, and all API is the same, it is just wrapped up in an ASP.NET AJAX control.
As for the Shape's GeoJSON, Telerik does not provide such data. Such can be found through public resources or by building one on your own. A quick Google search lead me to this resource. I believe it might be helpful for you—http://eric.clst.org/Stuff/USGeoJSON