SharePoint 2010 used to have issues while loading scripts dynamically upon Ajax request.
However this issue was fixed within the Microsoft Office 2010 October cumulative update – please make sure to apply this update.
Another thing to keep in mind is that SharePoint has issues when RadAjaxManager is declared at markup in a user control (You can face such issue in case you try to “Ajaxify” the RadScheduler).
You can overcome this by adding AjaxSettings programmatically
When you populate RadScheduler with data (the most commonly used datasource is SPList) you should set the DataSubjectField , DataStartField , DataEndField , DataKeyField of the RadScheduler to appropriate SPList fields.
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