Until the feature gets implemented please use the suggested solution here: http://www.telerik.com/support/kb/winforms/details/integrating-panzoom-trackball-and-lassozoom-controllers-in-radchartview

When combining scalebreaks and series stacking, the rendered chart does not match the data. 

See attached solution: The bar of the category "1/2016" has a length of 105 (as indicated by the tooltips) -- but the corresponding axis labeling shows a value of 37.  The scalebreak is off too (probably matching the wrong axis).

To reproduce:
-  Show the legend and the add remove series at runtime.
- The legend items must not have text.
 

To reproduce:
- Add three line series and only set their point size.
- At runtime remove the second series.
- The points color is not updated corectly.

Workaround
- Set colors in code like this:
lineSerie1.BorderColor = Color.Red;
lineSerie1.BackColor = Color.Red;

lineSerie2.BackColor = Color.Green;
lineSerie2.BorderColor = Color.Green;

lineSerie3.BackColor = Color.Blue;
lineSerie3.BorderColor = Color.Blue;

To reproduce: 
1. Add RadChartView with drill down and two RadCheckBox on the form
2. Subscribe to the ToggleStateChanged event of RadCheckBox and set the IsVisible property to true/false 
3. In handler of DrillDown event set the series`s IsVisible property to be equal to checkbox`s Checked property
4. In few cases the series are not visible when changing the IsVisible property and view. 

Unfortunately due to the nature of the issue we cannot provide a workaround for it. 

To reproduce:
- Subscribe to the SelectedPointChanged event and show a dialog in it.
- Start the chart and zoom in. Select a point, close the dialog and select a point again.

Workaround:
class MyChartSelectionController : ChartSelectionController
{
    protected override ActionResult OnMouseDown(MouseEventArgs e)
    {
        //return base.OnMouseDown(e);
        return Controller.Empty;
    }
    protected override ActionResult OnMouseUp(MouseEventArgs e)
    {
        if (!this.AllowSelect || this.SelectionMode == ChartSelectionMode.None)
        {
            return base.OnMouseUp(e);
        }

        DataPoint oldDataPoint = SelectedPoint;
        DataPoint newDataPoint = null;
        ChartSeries oldSeries = SelectedSeries;
        ChartSeries newSeries = null;
        DataPoint point = null;

        foreach (ChartSeries series in this.Area.Series)
        {
            point = series.HitTest(e.X, e.Y);
            if (point != null)
            {
                newDataPoint = point;
                newSeries = series;
                break;
            }
        }

        if (point == null)
        {
            return base.OnMouseUp(e);
        }

        ChartViewSelectedPointChangingEventArgs cancelArgs = new ChartViewSelectedPointChangingEventArgs(oldDataPoint, newDataPoint, oldSeries, newSeries, this.SelectionMode);
        OnSelectedPointChanging(cancelArgs);

        if (cancelArgs.Cancel == true)
        {
            return base.OnMouseUp(e);
        }

        if (oldDataPoint == newDataPoint)
        {
            oldDataPoint.IsSelected = !oldDataPoint.IsSelected;
            newDataPoint = null;
            SelectedPoint = null;
        }
        else
        {
            if (this.SelectionMode == ChartSelectionMode.SingleDataPoint && oldDataPoint != null)
            {
                oldDataPoint.IsSelected = false;
            }

            this.SelectedPoint = newDataPoint;
            this.SelectedPoint.IsSelected = !SelectedPoint.IsSelected;
        }

        ChartViewSelectedPointChangedEventArgs changedArgs = new ChartViewSelectedPointChangedEventArgs(oldDataPoint, newDataPoint, oldSeries, newSeries, this.SelectionMode);
        OnSelectedPointChanged(changedArgs);
    
        return base.OnMouseUp(e);
    }

   
}

To reproduce:
- Add a pie chart using the property builder and set the palette as well.

Workaround
- Set the palette in code:
 this.radChartView1.Area.View.Palette = KnownPalette.Metro;

To reproduce:
this.radChartView1.AreaType = ChartAreaType.Pie;
PieSeries series = new PieSeries();

series.DataPoints.Add(new PieDataPoint(50, "Germany"));

series.DataPoints.Add(new PieDataPoint(70, "United States"));

series.DataPoints.Add(new PieDataPoint(40, "France"));

for (int i = 0; i < 50; i++)
{
    series.DataPoints.Add(new PieDataPoint(1, "Item " + i));
}

series.ShowLabels = true;
series.DrawLinesToLabels = true;
this.radChartView1.Series.Add(series);
 this.radChartView1.ShowSmartLabels = true;

There are three ways in which null values can be handled:

1 . Zero. When this option is used, each null value is replaced with a zero. The data entry is not removed from the data collection. Only its original null/empty value is replaced with zero. 
2 . Gap. This option visually removes the regions for each set of empty(null) points. The data entry is not removed from the data collection. Essentially, it connects the points neighboring the null point (or the collection of empty values).
3 . Drop - this option clips, or visually removes each section/segment, corresponding to a set of empty points/values. 

The trackball does not work well when charting the dxf cad drawing of a circle or more complex shape

would be better for it to have cross hair mode,  as single point mode does not work (as it picks up a massive array of x,y points in the tooltip, making it unmanageable)

Showtrackball = true
SelectionMode = SingleDataPoint

How to reproduce: create a drill down chart with different area types on the different levels. 
The issue seems to be related to some series not implementing the ILegendInfoProvider interface.

Workaround:
A similar result as having a drill-down chart with series having different area types can be achieved manually using the ChartSelectionController. Please check the attached project and video file.

To reproduce:
public RadForm1()
{
    InitializeComponent();

    LineSeries lineSeries = new LineSeries();
    lineSeries.DataPoints.Add(new CategoricalDataPoint(40, "Jan"));
    lineSeries.DataPoints.Add(new CategoricalDataPoint(22, "Apr"));
    lineSeries.DataPoints.Add(new CategoricalDataPoint(12, "Jul"));
    lineSeries.DataPoints.Add(new CategoricalDataPoint(19, "Oct"));
    lineSeries.ShowLabels = true;
    this.radChartView1.Series.Add(lineSeries);

    LineSeries lineSeries2 = new LineSeries();
    lineSeries2.DataPoints.Add(new CategoricalDataPoint(13, "Jan"));
    lineSeries2.DataPoints.Add(new CategoricalDataPoint(15, "Apr"));
    lineSeries2.DataPoints.Add(new CategoricalDataPoint(17, "Jul"));
    lineSeries2.DataPoints.Add(new CategoricalDataPoint(22, "Oct"));
    lineSeries2.ShowLabels = true;
    this.radChartView1.Series.Add(lineSeries2);

    ((CartesianArea)this.radChartView1.View.Area).ShowGrid = true;

    int i = 1;
    foreach (DataPointElement dpe in this.radChartView1.Series[0].Children)
    {
        dpe.IsVisible = false; AnimatedPropertySetting setting = new AnimatedPropertySetting();
        setting.StartValue = false;
        setting.EndValue = true;
        setting.Property = UIChartElement.IsVisibleProperty;
        setting.ApplyDelay = 40 + 40 * i;
        setting.NumFrames = 2;
        setting.ApplyValue(dpe); i++;
    }i = 1;
    foreach (DataPointElement dpe in this.radChartView1.Series[1].Children)
    {
        dpe.IsVisible = false; AnimatedPropertySetting setting = new AnimatedPropertySetting();
        setting.StartValue = false; setting.EndValue = true;
        setting.Property = UIChartElement.IsVisibleProperty;
        setting.ApplyDelay = 60 + 60 * i;
        setting.NumFrames = 2;
        setting.ApplyValue(dpe); i++;
    }
}

Workaround:
Perform the animation in the Shown event.

To reproduce:

public Form1()
{
    InitializeComponent();

    Random rand = new Random();
    for (int i = 0; i < 3; i++)
    {
        LineSeries lineSeries = new LineSeries();    
        lineSeries.DataPoints.Add(new CategoricalDataPoint(rand.Next(-50, 50), "Jan"));
        lineSeries.DataPoints.Add(new CategoricalDataPoint(rand.Next(-50, 50), "Apr"));
        lineSeries.DataPoints.Add(new CategoricalDataPoint(rand.Next(-50, 50), "Jul"));
        lineSeries.DataPoints.Add(new CategoricalDataPoint(rand.Next(-50, 50), "Oct"));
        this.radChartView1.Series.Add(lineSeries);
    }

    this.radChartView1.ShowLegend = true;
    this.radChartView1.ChartElement.LegendPosition = LegendPosition.Bottom;

    ((LineSeries)this.radChartView1.Series[0]).LegendTitle = "S&P 500";
    ((LineSeries)this.radChartView1.Series[1]).LegendTitle = "MSCI Emerging Markets TR Index";
    ((LineSeries)this.radChartView1.Series[2]).LegendTitle = "Great ETF";
}


Workaround:

Font f = new Font("Times New Roman", 10f, FontStyle.Regular);

private void Form1_Load(object sender, EventArgs e)
{
    foreach (LegendItemElement item in this.radChartView1.ChartElement.LegendElement.StackElement.Children)
    {
        item.Font = f;
    }
}

To reproduce:

public Form1()
{
    InitializeComponent();
    this.radChartView1.AreaType = ChartAreaType.Polar;
    Random rand = new Random();
    for (int i = 0; i < 80; i++)
    {
        RadarLineSeries s = new RadarLineSeries();
        s.ShowLabels = true;
        for (int j = 0; j < 8; j++)
        {
            s.DataPoints.Add(new CategoricalDataPoint(rand.Next(1, 100), "X" + j));
        }
       
        this.radChartView1.Series.Add(s);
    }
    this.radChartView1.ShowSmartLabels = true;
}