Let me first note that once I open the page, I get the following error in the console, so you may want to look into that:
You have included the Google Maps API multiple times on this page. This may cause unexpected errors.
As for the RadWindows - you need to use the ClientIDs of the hyperlinks when the OpenerElementID property is used, as shown in this demo: http://demos.telerik.com/aspnet-ajax/window/examples/openandposition/defaultcs.aspx. The page uses the server IDs (e.g., hlHowTo) instead of the rendered HTML element id attribute (RadPanelBar1_i4_hlHowTo). ASP.NET changes the IDs of some elements when they are in INamingContainers and the other option you can consider is setting the ClientIDMode of those three hyperlinks to Static so ASP does not change their IDs.
This works on the simpler page because the link is not in a complex structure, so the ID attribute matches the ClientID attribute.
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