Change the Decimal symbol/separator  to "," and run Excel export for the RadPivotGrid. Note that all "0,00" cells are displayed as "1" in Excel and all decimal values are displayed without decimal separator.

Another scenario is when you change the Format in the Regional settings to Russia. Then, when exporting data, the decimal separator for the GrandTotal column is not correct ".", instead of ",". However, for the data cells it is OK.

Until the feature becomes available use the following workaround:

MyPivotGridChartDataProvider chartProvider = new MyPivotGridChartDataProvider(this.radPivotGrid1.PivotGridElement);
this.radPivotGrid1.ChartDataProvider = chartProvider;
this.radChartView1.DataSource = this.radPivotGrid1;
this.radChartView1.ShowLegend = true;
this.radPivotGrid1.ChartDataProvider.SeriesAxis = Telerik.Pivot.Core.PivotAxis.Rows;
this.radPivotGrid1.ChartDataProvider.GeneratedSeriesType = Telerik.WinControls.UI.GeneratedSeriesType.Line;

public class MyPivotGridChartDataProvider : PivotGridChartDataProvider
{
    public MyPivotGridChartDataProvider(RadPivotGridElement pivotGridElement)
        : base(pivotGridElement) { }

    public override void UpdateChartData()
    {
        base.UpdateChartData();

        foreach (ChartSeries series in this.ChartView.Series)
        {
            CartesianSeries cartesianSeries = series as CartesianSeries;
            if (cartesianSeries == null)
            {
                continue;
            }

            cartesianSeries.PointSize = new SizeF(7, 7);

            BindingList<PivotChartModelPoint> newData = new BindingList<PivotChartModelPoint>();
            BindingList<PivotDataPoint> points = cartesianSeries.DataSource as BindingList<PivotDataPoint>;

            foreach (PivotDataPoint point in points)
            {
                PivotChartModelPoint current = new PivotChartModelPoint() { Group = point.PivotGroup };
                if (point.Value != 0)
                {
                    current.Value = point.Value;
                }
                else
                {
                    current.Value = null;
                }

                newData.Add(current);
            }

            cartesianSeries.DataSource = null;

            cartesianSeries.CategoryMember = "Group";
            cartesianSeries.ValueMember = "Value";
            cartesianSeries.DataSource = newData;
        }
    }
}

public class PivotChartModelPoint
{
    public string Group{ get; set; }

    public double? Value { get; set; }
}

Workaround:

public Form1()
{
    InitializeComponent();

    this.radPivotFieldList1.ValuesControl.CreatingVisualListItem += Aggregates_CreatingVisualListItem;
}

private void Aggregates_CreatingVisualListItem(object sender, Telerik.WinControls.UI.CreatingVisualListItemEventArgs args)
{
    args.VisualItem = new MyPivotFieldListVisualItem(this.radPivotFieldList1.ViewModel);
}

    public class MyPivotFieldListVisualItem : PivotFieldListVisualItem
    {
        private FieldListViewModel viewModel;
 
        private CommandBarDropDownButton button;
        private RadMenuItem sumMenuItem;
        private RadMenuItem avgMenuItem;
        private RadMenuItem countMenuItem;
 
        public MyPivotFieldListVisualItem(FieldListViewModel viewModel)
            : base(viewModel)
        {
            this.viewModel = viewModel;
        }
 
        protected override void CreateChildElements()
        {
            base.CreateChildElements();
 
            this.sumMenuItem = this.GetType().BaseType
                .GetField("sumMenuItem", BindingFlags.Instance | BindingFlags.NonPublic)
                .GetValue(this) as RadMenuItem;
 
            this.avgMenuItem = this.GetType().BaseType
              .GetField("avgMenuItem", BindingFlags.Instance | BindingFlags.NonPublic)
              .GetValue(this) as RadMenuItem;
 
            this.countMenuItem = this.GetType().BaseType
              .GetField("countMenuItem", BindingFlags.Instance | BindingFlags.NonPublic)
              .GetValue(this) as RadMenuItem;
 
            if (sumMenuItem != null && avgMenuItem != null && countMenuItem != null)
            {
                sumMenuItem.Click += OnAggregateFunctionClick;
                avgMenuItem.Click += OnAggregateFunctionClick;
                countMenuItem.Click += OnAggregateFunctionClick;
            }
 
            this.button = this.GetType().BaseType
             .GetField("button", BindingFlags.Instance | BindingFlags.NonPublic)
             .GetValue(this) as CommandBarDropDownButton;
 
            RadMenuItem aggregateOptionsMenuItem = this.GetType().BaseType
                .GetField("aggregateOptionsMenuItem", BindingFlags.Instance | BindingFlags.NonPublic)
                .GetValue(this) as RadMenuItem;
 
            aggregateOptionsMenuItem.Click += aggregateOptionsMenuItem_Click;
 
            RadMenuItem numberFormatMenuItem = this.GetType().BaseType
                .GetField("numberFormatMenuItem", BindingFlags.Instance | BindingFlags.NonPublic)
                .GetValue(this) as RadMenuItem;
 
            numberFormatMenuItem.Click += numberFormatMenuItem_Click;
        }
 
        private void numberFormatMenuItem_Click(object sender, EventArgs e)
        {
            Value value = (this.Data.DataBoundItem as Value);
            if (value == null)
            {
                return;
            }
 
            MyNumberFormatOptionsDialog dialog =  new MyNumberFormatOptionsDialog();
            dialog.ThemeName = this.GetThemeName();
 
            QueryableAggregateDescription queryableAggregateDescription = (value.Description as QueryableAggregateDescription);
            if (queryableAggregateDescription != null)
            {
                dialog.LoadQueryableSettings(queryableAggregateDescription);
            }
 
            System.Windows.Forms.DialogResult result = dialog.ShowDialog();
 
            if (result == System.Windows.Forms.DialogResult.OK)
            {
                queryableAggregateDescription.StringFormat = dialog.SelectedStringFormat;
                this.viewModel.ExecuteUpdate();
            }
        }
 
        private void aggregateOptionsMenuItem_Click(object sender, EventArgs e)
        {
            MyAggregateOptionsDialog dialog = new MyAggregateOptionsDialog();
            dialog.ThemeName = this.GetThemeName();
 
            Value value = (this.Data.DataBoundItem as Value);
            if (value != null)
            {
                QueryablePropertyAggregateDescriptionBase queryableAggregateDescription = (value.Description as QueryablePropertyAggregateDescriptionBase);
                if (queryableAggregateDescription != null)
                {
                    dialog.LoadQueryableSettings(queryableAggregateDescription);
                }
 
                System.Windows.Forms.DialogResult result = dialog.ShowDialog();
                if (result == System.Windows.Forms.DialogResult.OK)
                {
                    queryableAggregateDescription.AggregateFunction = dialog.SelectedQueryableAggregateFunction;
                    queryableAggregateDescription.CustomName = dialog.CustomName;
 
                    this.Synchronize();
                    this.viewModel.ExecuteUpdate();
                }
            }
        }
 
        private void OnAggregateFunctionClick(object sender, EventArgs e)
        {
            Value value = (this.Data.DataBoundItem as Value);
            string function = ((RadMenuItem)sender).Text;
 
            if (value != null && this.SetNewAggregateFunction(value.Description, function))
            {
                this.Synchronize();
                this.viewModel.ExecuteUpdate();
            }
        }
 
        private bool SetNewAggregateFunction(IAggregateDescription description, string function)
        {
            QueryablePropertyAggregateDescriptionBase queryableDescription = (description as QueryablePropertyAggregateDescriptionBase);
            if (queryableDescription != null)
            {
                switch (function)
                {
                    case "Sum":
                        queryableDescription.AggregateFunction = QueryableAggregateFunction.Sum;
                        break;
                    case "Count":
                        queryableDescription.AggregateFunction = QueryableAggregateFunction.Count;
                        break;
                    case "Average":
                        queryableDescription.AggregateFunction = QueryableAggregateFunction.Average;
                        break;
                    default:
                        return false;
                }
 
                return true;
            }
 
            return false;
        }
 
        protected override void SynchronizeProperties()
        {
            base.SynchronizeProperties();
 
            Value value = (this.Data.DataBoundItem as Value);
            Label label = (this.Data.DataBoundItem as Label);
 
            if (value != null)
            {
#if !NETFX2
                QueryablePropertyAggregateDescription queryableDescription = (value.Description as QueryablePropertyAggregateDescription);
                if (queryableDescription != null)
                {
                    this.sumMenuItem.IsChecked = queryableDescription.AggregateFunction == QueryableAggregateFunction.Sum;
                    this.countMenuItem.IsChecked = queryableDescription.AggregateFunction == QueryableAggregateFunction.Count;
                    this.avgMenuItem.IsChecked = queryableDescription.AggregateFunction == QueryableAggregateFunction.Average;
                }
#endif
            }
        }
 
        private string GetThemeName()
        {
            if (this.ElementTree == null)
            {
                return string.Empty;
            }
 
            RadControl control = this.ElementTree.Control as RadControl;
 
            return control != null ? control.ThemeName : string.Empty;
        }
    }
 
public class MyAggregateOptionsDialog : AggregateOptionsDialog
    {
        private RadListControl listAggregateFunctions;
        private RadLabel labelFieldName;
        private RadTextBox textBoxCustomName;

        public MyAggregateOptionsDialog()
        {
            this.listAggregateFunctions = this.GetType().BaseType
               .GetField("listAggregateFunctions", BindingFlags.Instance | BindingFlags.NonPublic)
               .GetValue(this) as RadListControl;

            this.labelFieldName = this.GetType().BaseType
                .GetField("labelFieldName", BindingFlags.Instance | BindingFlags.NonPublic)
                .GetValue(this) as RadLabel;

            this.textBoxCustomName = this.GetType().BaseType
                .GetField("textBoxCustomName", BindingFlags.Instance | BindingFlags.NonPublic)
                .GetValue(this) as RadTextBox;
        }

        private readonly IList<QueryableAggregateFunction> availableQueryableAggregateFunctions = new List<QueryableAggregateFunction>()
            {
                QueryableAggregateFunction.Sum,
                QueryableAggregateFunction.Count,
                QueryableAggregateFunction.Average,
                QueryableAggregateFunction.Max,
                QueryableAggregateFunction.Min
            };

        public virtual QueryableAggregateFunction SelectedQueryableAggregateFunction
        {
            get
            {
                return (QueryableAggregateFunction)this.listAggregateFunctions.SelectedValue;
            }
        }

        public virtual void LoadQueryableSettings(QueryablePropertyAggregateDescriptionBase aggregateDescription)
        {
            if (this.listAggregateFunctions.DataSource != null)
            {
                this.listAggregateFunctions.DataSource = availableQueryableAggregateFunctions;
            }

            this.listAggregateFunctions.SelectedValue = aggregateDescription.AggregateFunction;
            this.labelFieldName.Text = aggregateDescription.PropertyName;
            this.Text = String.Format("{0}{1}{2}", "Aggregate Options (", aggregateDescription.PropertyName, ")");
            this.textBoxCustomName.Text = aggregateDescription.CustomName;
        }
    }

public class MyNumberFormatOptionsDialog : NumberFormatOptionsDialog
    {
        private TextBox textBox;

        public MyNumberFormatOptionsDialog()
        {
            RadDropDownList dropDownListFormat = this.GetType().BaseType
                   .GetField("dropDownListFormat", BindingFlags.Instance | BindingFlags.NonPublic)
                   .GetValue(this) as RadDropDownList;

            this.textBox = (TextBox)dropDownListFormat.DropDownListElement.EditableElement.TextBox.TextBoxItem.HostedControl;
        }

        public virtual void LoadQueryableSettings(QueryableAggregateDescriptionBase aggregateDescription)
        {
            this.textBox.Text = aggregateDescription.StringFormat;
            this.Text = String.Format(PivotGridLocalizationProvider.CurrentProvider.GetLocalizedString(PivotStringId.NumberFormatOptionsDialogFormatOptionsDescription),
                aggregateDescription.DisplayName);
            this.textBox.Select(this.textBox.Text.Length, 0);
            this.textBox.Focus();
        }
    }

Argument exception when a specific layout is loaded:
"An item with the same key has already been added."

To reproduce:

1. Add a RadPivotGrid and  change its theme to TelerikMetro. This theme uses Segoe UI font for its cells.
2. Export the RadPivotGrid.
3. You will notice that the font is applied to some of the cells, but for others, e.g. Grand Total the default font is set to Microsoft Sans Serif

Second scenario: use Demo application PivotGrid >> Export to Excel example. Use ControlDefault theme.
1. Ctrl + H to show the spy.  Check font for row  "Jun-1 >> Sum of Net", column "Printer stand >> 1 Free with 10".  The font is Segoe UI.
2. Run the export and check the same cell in Excel. Its font is Microsoft Sans Serif.

Workaround: use the PivotExcelCellFormatting event to specify the font.

To reproduce:
- Add calculated field
- Try to set its number format, by clicking the Number Format option in the context menu in the field list (see image)

Workaround:
 Private Sub RadPivotGrid1_CellFormatting(sender As Object, e As UI.PivotCellEventArgs) Handles RadPivotGrid1.CellFormatting
        If e.CellElement.Column.Name = "Commission" Then
            e.CellElement.Text = String.Format(System.Threading.Thread.CurrentThread.CurrentUICulture, "{0:C}", e.CellElement.Value)
        End If
    End Sub

Workaround: 
PivotExportToExcelML.ExportVisualSettings = false;

Workaround: 

private void radPivotGrid1_GroupDescriptorElementCreating(object sender, Telerik.WinControls.UI.GroupDescriptorElementCreatingEventArgs e)
{
    e.GroupDescriptorElement.FilterPopup.PopupOpened -= FilterPopup_PopupOpened;
    e.GroupDescriptorElement.FilterPopup.PopupOpened += FilterPopup_PopupOpened;
}

private void FilterPopup_PopupOpened(object sender, EventArgs args)
{
    PivotGroupFilterPopup filterPopup = (PivotGroupFilterPopup)sender;
    RadTreeView tree = filterPopup.TreeViewMenuItem.TreeElement.TreeView;
    int height = this.CalculateHeight(tree);
    if (height > tree.Height)
    {
        ((RadScrollBarElement)tree.TreeViewElement.Children[2]).Value = 0;
        ((RadScrollBarElement)tree.TreeViewElement.Children[2]).Maximum = height;
        ((RadScrollBarElement)tree.TreeViewElement.Children[2]).Visibility = Telerik.WinControls.ElementVisibility.Visible;
    }
}

private int CalculateHeight(RadTreeView tree)
{
    int height = 0;
    for (int i = 0; i < tree.Nodes[0].Nodes.Count + 1; i++)
    {
        height += tree.ItemHeight;
    }

    return height;
}

Workaround:
public Form1()
{
    InitializeComponent();
    this.radPivotGrid1.GroupDescriptorElementCreating += radPivotGrid1_GroupDescriptorElementCreating;
}

private void radPivotGrid1_GroupDescriptorElementCreating(object sender, Telerik.WinControls.UI.GroupDescriptorElementCreatingEventArgs e)
{
    e.GroupDescriptorElement.FilterPopup.PopupOpened -= FilterPopup_PopupOpened;
    e.GroupDescriptorElement.FilterPopup.PopupOpened += FilterPopup_PopupOpened;
}

private void FilterPopup_PopupOpened(object sender, EventArgs args)
{
    PivotGroupFilterPopup filterPopup = (PivotGroupFilterPopup)sender;
    RadTreeView tree = filterPopup.TreeViewMenuItem.TreeElement.TreeView;

    ((RadScrollBarElement)tree.TreeViewElement.Children[2]).Value = 10;
    ((RadScrollBarElement)tree.TreeViewElement.Children[2]).Value = 0;
}

To reproduce:
Resize some of the columns in PivotGrid and then export it with PivotExporttoExcelML. All columns in exported file have the same width.
Workaround:
Use PivotGridSpreadExport.

Workaround:

private IList<PivotGroupNode> collapsedRowsNodes;
private void customMenuItem_Click(object sender, EventArgs e)
{
    PivotGridSpreadExport spreadExport = new PivotGridSpreadExport(pivotGrid);
    spreadExport.ExportCompleted += spreadExport_ExportCompleted;
    spreadExport.ExportFlatData = true;

    this.collapsedRowsNodes = new List<PivotGroupNode>();
    PivotGridGroupTraverser rowTraverser = (PivotGridGroupTraverser)this.pivotGrid.PivotGridElement.RowScroller.Traverser.GetEnumerator();
    while (rowTraverser.MoveNext())
    {
        PivotGroupNode current = rowTraverser.Current;
        if (!current.Expanded)
        {
            this.collapsedRowsNodes.Add(current);
            current.Expanded = true;
        }
    }

    spreadExport.RunExport(@"..\..\export.xlsx", new SpreadExportRenderer());
}

private void spreadExport_ExportCompleted(object sender, EventArgs e)
{
    foreach (PivotGroupNode node in this.collapsedRowsNodes)
    {
        node.Expanded = false;
    }
}

You save 2 config, one with Report filter (1), one without (2), if you load first (1), if puts report filter correctly, but if you load then (2) - report filter still as on (1).
Also, if you load config with ShowFilterArea=true - it  stays visible if you load another config with ShowFilterArea=true 

Hello Alex,

While investigating the reported behavior I managed to isolate an issue in the Save/Load API of RadPivotGrid regarding the ShowFilterArea property. The default value of this property is not serialized, however this can be altered by adding a serialization meta data to the XmlSerializationInfo instance of the pivot. In this scenario the engine did not respect the added new data. Here is the feedback item and you can subscribe to it: http://feedback.telerik.com/Project/154/Feedback/Details/196273-fix-radpivotgrid-the-saveloadlayout-string-overload-does-not-use-the-radpivotg. The item is already in development and a permanent fix will be available with our next release.

Regarding the empty filter descriptions, in order to serialize them one should work with a DataProviderSerializer class. Currently our engine does not save the empty filters and we will consider modifying it so that even if the collection is empty it also be serialized.

I am attaching to this post a sample project with which you would be able to achieve both of your tasks. Please note that the serialization API of the LocalDataSourceProvider uses the DataContract and you would need to use our .NET 4.0 assemblies.

I hope this helps. In case you need additional assistance please write here or open a support ticket.

Regards, 
Hristo

How to reproduce check the attached project and video

Workaround: handle the UpdateCompleted event and explicitly set the properties to true

public LocalDataSourceSerializerForm()
{
    InitializeComponent();

    this.radPivotGrid1.AutoExpandColumnHeaders = false;
    this.radPivotGrid1.AutoExpandRowHeaders = false;

    this.radPivotGrid1.UpdateCompleted += radPivotGrid1_UpdateCompleted;
}

private void radPivotGrid1_UpdateCompleted(object sender, EventArgs e)
{
    this.radPivotGrid1.AutoExpandColumnHeaders = true;
    this.radPivotGrid1.AutoExpandRowHeaders = true;
}

Until the feature gets implemented use custom PivotGridPrintStyle:

Public Class MyPivotGridPrintStyle
    Inherits PivotGridPrintStyle

    Const MIN_SPACE As Integer = 1

    Public Overrides Sub DrawPage(drawArea As Rectangle, graphics As Graphics, pageNumber As Integer)

        If Me.PivotGrid.ColumnHeaderHeight > MIN_SPACE Then
            MyBase.DrawPage(drawArea, graphics, pageNumber)

        Else
            Dim x As Integer = drawArea.X
            Dim y As Integer = drawArea.Y
            Dim scale As SizeF = DirectCast(Me.GetType().BaseType.GetMethod("GetScaleFactors", BindingFlags.Instance Or BindingFlags.NonPublic).Invoke(Me, New Object() {drawArea}), SizeF)

            Dim startColumn As Integer = DirectCast(Me.GetType().BaseType.GetMethod("GetStartColumn", BindingFlags.Instance Or BindingFlags.NonPublic).Invoke(Me, New Object() {pageNumber, drawArea, scale.Width}), Integer)
            Dim endColumn As Integer = DirectCast(Me.GetType().BaseType.GetMethod("GetEndColumn", BindingFlags.Instance Or BindingFlags.NonPublic).Invoke(Me, New Object() {startColumn, drawArea, scale.Width}), Integer)
            Dim startRow As Integer = DirectCast(Me.GetType().BaseType.GetMethod("GetStartRow", BindingFlags.Instance Or BindingFlags.NonPublic).Invoke(Me, New Object() {pageNumber, drawArea, scale.Height}), Integer)
            Dim endRow As Integer = DirectCast(Me.GetType().BaseType.GetMethod("GetEndRow", BindingFlags.Instance Or BindingFlags.NonPublic).Invoke(Me, New Object() {startRow, drawArea, scale.Height}), Integer)

            If Me.PivotGrid.ColumnHeaderHeight <= MIN_SPACE Then
                startRow += 1
            End If

            For i As Integer = startRow To endRow
                x = drawArea.X
                Dim maxHeight As Integer = 0

                For j As Integer = startColumn To endColumn
                    Dim columnWidths = DirectCast(Me.GetType().BaseType.GetField("columnWidths", BindingFlags.Instance Or BindingFlags.NonPublic).GetValue(Me), List(Of Integer))
                    Dim rowHeights = DirectCast(Me.GetType().BaseType.GetField("rowHeights", BindingFlags.Instance Or BindingFlags.NonPublic).GetValue(Me), List(Of Integer))

                    Dim elementRect As New Rectangle(x, y, columnWidths(j), rowHeights(i))
                    Dim printElement As RadPrintElement = Me.GetPrintElementForCell(i, j)
                    printElement.ScaleTransform = scale
                    Dim transformedRect As RectangleF = printElement.GetTransformedBounds(elementRect)

                    Me.PrintElement(printElement, drawArea, elementRect, graphics)
                    x += CInt(Math.Floor(transformedRect.Width))
                    maxHeight = Math.Max(maxHeight, CInt(Math.Floor(transformedRect.Height)))
                Next

                y += maxHeight
            Next
        End If
    End Sub

End Class

Workaround:
private void PrintPivotGrid()
{
    MyPivotGridPrintStyle style = new MyPivotGridPrintStyle();
    style.LayoutType = PivotLayout.Tabular;
    this.radPivotGrid1.PrintStyle = style;
    this.radPivotGrid1.PrintPreview();
}

public class MyPivotGridPrintStyle : PivotGridPrintStyle
{
    public override void Initialize()
    {
        base.Initialize();

        FieldInfo fiColumnWidths = this.GetType().BaseType.GetField("columnWidths", BindingFlags.Instance | BindingFlags.NonPublic);
        List<int> columnWidths = (List<int>)fiColumnWidths.GetValue(this);
        RadPivotGridElement pivotGrid = (RadPivotGridElement)this.GetType().BaseType.GetField("pivotGrid", BindingFlags.Instance | BindingFlags.NonPublic)
                                                                                    .GetValue(this);

        for (int i = 0; i < pivotGrid.RowDescriptorsArea.Children.Count; i++)
        {
            RadElement descriptor = pivotGrid.RowDescriptorsArea.Children[i];
            columnWidths[i] = descriptor.Size.Width;
        }
    }
}

How to reproduce:
   var data = this.dbContext.Orders.Where(o => o.OrderID > 10500).Select(o => new
            {
                Id = o.OrderID,
                OrderDate = o.OrderDate,
                ShipDate = o.ShippedDate,
                Freight = o.Freight
            }).ToArray();

this.localDataProvider = new LocalDataSourceProvider() {ItemsSource = data};

Workaround:
1. Instead of  ToArray call ToList
var data = this.dbContext.Orders.Where(o => o.OrderID > 10500).Select(o => new
{
    Id = o.OrderID,
    OrderDate = o.OrderDate,
    ShipDate = o.ShippedDate,
    Freight = o.Freight
}).ToList();

this.localDataProvider = new LocalDataSourceProvider() {ItemsSource = data};

2. Call the ToArray method but do not create anonymous objects.
var data = this.dbContext.Orders.Where(o => o.OrderID > 10500).Select(o => new PivotModel
{
    Id = o.OrderID,
    OrderDate = o.OrderDate,
    ShipDate = o.ShippedDate,
    Freight = o.Freight
}).ToArray();

this.localDataProvider = new LocalDataSourceProvider() {ItemsSource = data};

public class PivotModel
{
    public int Id { get; set; }

    public DateTime? OrderDate { get; set; }

    public DateTime? ShipDate { get; set; }

    public decimal? Freight { get; set; }
}