Workaround:

Use the new PivotGridSpreadExport

To reproduce: 

- Set the ExportFlatData property to true

- Export the grid using PivotExportToExcelML

Workaround: If possible add the label filters with code
PropertyGroupDescription dateGroupDescription = new PropertyGroupDescription();
dateGroupDescription.PropertyName = "Date";

LabelGroupFilter filter = new LabelGroupFilter();
ComparisonCondition condition = new ComparisonCondition
{
    Condition = Telerik.Pivot.Core.Filtering.Comparison.IsGreaterThan,
    Than = new DateTime(2010, 6, 6)
};
filter.Condition = condition;
dateGroupDescription.GroupFilter = filter;

this.provider.RowGroupDescriptions.Add(dateGroupDescription);

The best solution would be to have cells in Excel with the correct data type and formatted values. This can be achieved with an additional property similar to RadGridView. At the moment data cells which are created from aggregate descriptions with an applied StringFormat property are exported as text and they do not persist the formatting which is not correct.

 A possible workaround is to set the ExportVisualSettings property of the PivotGridSpreadExport object to true so that the formatting event to fire. Then in the CellFormatting event one can set the FormatString this way:
        private void SpreadExport_CellFormatting(object sender, PivotGridSpreadExportCellFormattingEventArgs e)
        {
            if (e.Cell.Text.StartsWith("$"))
            {
                e.Cell.FormatString = "$ #.00";
            }
            else if (e.Cell.Text.Contains("€"))
            {
                e.Cell.FormatString = "#.00 €";
            }
        }

PivotGridSpreadExportCellFormattingEventArgs, however, does not provide information about the actual aggregate of the data cell, so the applied number format on the aggregate cannot be obtained in the formatting event.

Add functionality which will allow the end users to edit the aggregated data. The new values should be passed back to the business logic of the application which will decide how to divide the new value across underlying records.

When a filter dialog is shown (Report Filter or Label Filter) for OLAP Hierarchy, it contains the items only for the selected level. Instead items from all levels could be visible, so you won't have to open additional dialogs to filter them (show them like a tree).

One should be able to move the selected cell and scroll with the arrow keys. The attached project features a solution for moving the currently selected cell using the arrow keys.

The TelerikData.dll and ChartView.dll should only be referenced when one needs to use the Export or Bind-to-ChartView functionality respectively. With the current implementation, when someone wants to merge the PivotGrid.dll in their application, the TelerikData.dll and ChartView.dll will always be required to merge because assemblies are resolved statically when merging.

Currently the AdomdDataProvider supports only AdomdClient version 10.0 which supports Microsoft SQL Server 2008. Add support for newer versions.

Description:
One should be able to resize row header cells programmatically as it is with the mouse currently.

AutoSizeRows property which allows autosizing both header rows and data rows.