I tried both links and was able to reproduce the problem only once, and I noticed that at this moment there was an interrupted AJAX request initiated by RadFileExplorer, I am not quite sure why this request was aborted, and I was not able to reproduce the problem once again.
However, when I decided to try it again yesterday, the links were changed and I was unable to examine the page again. Since you are not able to reproduce the problem locally and are able to observe it on the server, could you please check if there is an aborted AJAX request every time the problem occurs. If so, try to disable the AJAX on the page and test again. If the explorer keeps 'hanging' and its internal AJAX requests keep getting aborted, I would recommend you to contact the hosting company and ask for server logs.
the Telerik team
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to their blog feed