What I would like is to be able to export to a named sheet and keep the other sheets in file. For example:
"Sheet 1" (with new values), "Sheet2" (with old values)

Using your current naming convention, the Option might be named FileExportMode.CreateOrOverrideSheet

To reproduce the problem, use the following setup for RadPivotGrid:

        public RadForm1()
        {
            InitializeComponent();

            DataTable table = new DataTable();
            table.Columns.Add("Name", typeof(string));
            table.Columns.Add("Salary", typeof(int));
            table.Columns.Add("Title", typeof(string));
            table.Rows.Add("John",1200,"Accountant");
            table.Rows.Add("Ana", 800, "Accountant");
            table.Rows.Add("Sam", 2500, "Manager");
            table.Rows.Add("Tom", 1300, "Manager");

            this.radPivotGrid1.RowGroupDescriptions.Add(new PropertyGroupDescription() { PropertyName = "Title"});
            this.radPivotGrid1.RowGroupDescriptions.Add(new PropertyGroupDescription() { PropertyName = "Name" });
            this.radPivotGrid1.AggregateDescriptions.Add(new PropertyAggregateDescription() { PropertyName = "Salary", AggregateFunction = AggregateFunctions.Sum }); 
         
            this.radPivotGrid1.DataSource = table;
        }

Follow the steps:

1. Filter the child group ("Name") >> Salary>1000.

This is the result of the applied filter:

2.  Filter the parent group ("Title") >> Salary>1500.

After applying the filter, the observed result is that the Accountant group is still displayed even though it should be filtered and hidden (like in Excel):

Observed result:

Expected result:

When the RowGrandTotalsPosition and ColumnGrandTotalsPosition for RadPivotGrid are set to First, it would be suitable to offers options for keeping the row/column grand totals always visible in the view after scrolling:

In this case, we have Field1 and Field2 and some of the data source items will have equal values for both properties. In this case, the equal value is an empty string.

When we filter the rows by removing the empty string value, it will also remove the column which has the same value(empty string).

The result is not correct.

When using Crystal or CrystalDark themes, the resize cursor is not showing to widen/shrink the columns:

Expected:

Actual:

My pivot grid data size is 90,388 rows, and I export data to xlsx format with SheetName = "data".

The output file generated in this case (correctly) has 65536 rows on sheet "data" and the remaining 24852 rows on the sheet "data_2" (since SheetMaxRows = 65536 and total rows > SheetMaxRows, second sheet "data_2" is added automatically).

But the rows on the sheet "data_2" are written starting from line number 65538. The data on sheet "data_2" starts on line 65538 and goes till line 90389.

Expected:

Actual:

Workaround; use the following custom renderer:

        public class MyRenderer : SpreadExportRenderer
        {
            public override void CreateCellSelection(int rowIndex, int columnIndex)
            {
                if (rowIndex > (int)Telerik.WinControls.UI.Export.ExcelMaxRows._65536)
                {
                    rowIndex = rowIndex % (int)Telerik.WinControls.UI.Export.ExcelMaxRows._65536 - 1;
                }
                else
                {
                    rowIndex = rowIndex % (int)Telerik.WinControls.UI.Export.ExcelMaxRows._65536;
                }
                base.CreateCellSelection(rowIndex, columnIndex);
            }
        }

Here is my code for localizing the Sum aggregate function. The obtained result is a partial translation:

        public RadForm1()
        {
            PivotGridLocalizationProvider.CurrentProvider = new MyEnglishPivotGridLoclizationProvider();
            InitializeComponent();
        }

        private void RadForm1_Load(object sender, EventArgs e)
        {
            this.ordersTableAdapter.Fill(this.nwindDataSet.Orders);

            this.radPivotGrid1.RowGroupDescriptions.Add(new DateTimeGroupDescription() { PropertyName = "OrderDate", Step = DateTimeStep.Year, GroupComparer = new GroupNameComparer() });
            this.radPivotGrid1.RowGroupDescriptions.Add(new DateTimeGroupDescription() { PropertyName = "OrderDate", Step = DateTimeStep.Quarter, GroupComparer = new GroupNameComparer() });
            this.radPivotGrid1.RowGroupDescriptions.Add(new DateTimeGroupDescription() { PropertyName = "OrderDate", Step = DateTimeStep.Month, GroupComparer = new GroupNameComparer() });
            this.radPivotGrid1.ColumnGroupDescriptions.Add(new PropertyGroupDescription() { PropertyName = "EmployeeID", GroupComparer = new GrandTotalComparer() });
            this.radPivotGrid1.AggregateDescriptions.Add(new PropertyAggregateDescription() { PropertyName = "Freight", AggregateFunction = AggregateFunctions.Sum });
            this.radPivotGrid1.AggregateDescriptions.Add(new PropertyAggregateDescription() { PropertyName = "Freight", AggregateFunction = AggregateFunctions.Count });
            this.radPivotGrid1.FilterDescriptions.Add(new PropertyFilterDescription() { PropertyName = "ShipCountry", CustomName = "Country" });
            this.radPivotGrid1.DataSource = this.ordersBindingSource;
        }

        class MyEnglishPivotGridLoclizationProvider : PivotGridLocalizationProvider
        {
            public override string GetLocalizedString(string id)
            {
                switch (id)
                {
                    case PivotStringId.Sum:
                        return "Soma"; 
                    default:
                        return base.GetLocalizedString(id);
                }
            }
        }

The "Sort" item doesn't seem to be relevant for the report filter. It should be removed from the menu items. However, for the "Hide" item it can be added logic for removing the filter:

The error is reproducible in the First look example of RadPivotGrid:

Hello,

I am using the pivot grid control would like to know if it is possible to add a start and end to the grouping?

My pivot grid looks like this: I would like the user to be able to specify a start and end for the grouping.

Excel has this option:

How can I replicate this functionality?

As a user I want to hide the Grand Totals for specific groups:

Check the attached screenshot:

Workaround:

Use the new PivotGridSpreadExport

To reproduce: 

- Set the ExportFlatData property to true

- Export the grid using PivotExportToExcelML

How to reproduce: see the attached video

Workaround:
public partial class Form2 : Form
{
    public Form2()
    {
        InitializeComponent();

        this.radPivotFieldList1.DragDropService = new CustomPivotFieldListDragDropService(this.radPivotFieldList1);
    }

    private void Form2_Load(object sender, EventArgs e)
    {
        // TODO: This line of code loads data into the 'nwindDataSet.Orders' table. You can move, or remove it, as needed.
        this.ordersTableAdapter.Fill(this.nwindDataSet.Orders);

    }
}

public class CustomPivotFieldListDragDropService : PivotFieldListDragDropService
{
    private RadPivotFieldList fieldList;
    private Telerik.WinControls.UI.PivotFieldList.FieldPayload payload;

    public CustomPivotFieldListDragDropService(RadPivotFieldList fieldList)
        : base(fieldList)
    {
        this.fieldList = fieldList;
    }

    protected override void PerformStart()
    {
        base.PerformStart();

        Telerik.WinControls.UI.PivotFieldList.IField draggedField = this.GetField(this.Context);

        if (draggedField == null)
        {
            this.Stop(false);
            return;
        }

        this.payload = new Telerik.WinControls.UI.PivotFieldList.FieldPayload(draggedField);
    }

    protected override void OnPreviewDragOver(RadDragOverEventArgs e)
    {
        RadElement targetElement = this.DropTarget as RadElement;
        Telerik.WinControls.UI.PivotFieldList.IField targetField = this.GetField(targetElement);

        if (targetElement != null && targetElement.ElementTree.Control == this.fieldList.ReportFiltersControl && this.payload != null)
        {
            foreach (Telerik.WinControls.UI.PivotFieldList.IField field in this.fieldList.ViewModel.Filters)
            {
                if (field.FieldInfo == payload.DraggedField.FieldInfo &&  this.Context is TreeNodeElement ))
                {
                    e.CanDrop = false;
                    this.payload.SetDestination(null);
                    this.payload.RemoveFromSource = false;

                    return;
                }
            }
        }

        base.OnPreviewDragOver(e);
    }

    private Telerik.WinControls.UI.PivotFieldList.IField GetField(object context)
    {
        RadListVisualItem listItem = context as RadListVisualItem;
        TreeNodeElement treeItem = context as TreeNodeElement;
        PivotFieldListItemButton button = context as PivotFieldListItemButton;

        if (button != null)
        {
            listItem = button.Owner;
        }

        Telerik.WinControls.UI.PivotFieldList.IField field1 = null, field2 = null;
        if (listItem != null && listItem.Data != null)
        {
            field1 = listItem.Data.DataBoundItem as Telerik.WinControls.UI.PivotFieldList.IField;
        }

        if (treeItem != null && treeItem.Data != null)
        {
            field2 = treeItem.Data.DataBoundItem as Telerik.WinControls.UI.PivotFieldList.IField;
        }

        return field1 ?? field2;
    }
}

How to reproduce: 
Me.RadPivotGrid1.DataSource = Nothing

Workaround: 
DirectCast(Me.RadPivotGrid1.DataProvider, LocalDataSourceProvider).ItemsSource = Nothing
Dim viewModel = Me.RadPivotGrid1.PivotGridElement.GetType().GetField("viewModel", BindingFlags.Instance Or BindingFlags.NonPublic).GetValue(Me.RadPivotGrid1.PivotGridElement)
viewModel.GetType().GetProperty("DataProvider").SetValue(viewModel, Nothing)