The task of importing the spreadsheet from google to the given database should be implemented by the developer and is not related to the RadControls in any way.
On using a Gantt chart - I am afraid that a pure Gantt chart is not available in the ASP.NET AJAX suite at the moment. You can examine the following demo to see if it fits your needs, however: http://demos.telerik.com/aspnet-ajax/chart/examples/skinning/misc/defaultcs.aspx
. You can also consider the RadGanttView for Silverlight: http://www.telerik.com/help/silverlight/radganttview-overview.html
and you can see it in action in the SIlverlight demos: http://demos.telerik.com/silverlight/#GanttView/FirstLook
the Telerik team
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