Are you using a WebService to load the contents for the tooltips? I am asking this because the webservice returns only the HTML string with the markup and thus scripts, stylesheets and event handlers are not attached and therefore complex controls cannot be used directly with it - they rely on dynamically generated scripts and stylesheet references, most of which is done by the framework. If this is you case I'd advise that you revert to using the AJAX request method
of obtaining the new data. This is also the case in the linked demo - it uses AJAX to load the user control.
the Telerik team
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