When the EnableConfigurationPanel is enabled for the PivotGrid and is being rendered without having data bound to it, the "System.NullReferenceException: Object reference not set to an instance of an object." exception will be thrown.
To replicate the problem, add the following PivotGrid declaration to the page without binding data to it:
<telerik:RadPivotGrid ID="RadPivotGrid1" runat="server" EnableConfigurationPanel="true">
</telerik:RadPivotGrid>
The appearance problem can be seen on http://demos.telerik.com/aspnet-ajax/pivotgrid/examples/firstlook/defaultcs.aspx.
Click on the filter icon for Product name, you will find that the save and cancel buttons are off-screen. And if you hover over Label Filters or Value Filters the window is not wide enough to fit the popout menus that show:
Biff export (RadTreeList, RadGrid, RadPivotGrid) throws an "Out of Memory" exception when exporting from application hosted on Azure.