Workaround:
1. Explicitly set the font of the parent of the controls.
2. Use a custom theme with the FontSegoeUI8.25 repository: check the attached screenshot

Workaround: 
1. Explicitly set the font of the checkbox with code.
this.radCheckBox1.Font = new Font("Segoe UI", 9.0f, FontStyle.Regular);

2. Use the attached custom theme.

To reproduce:
1. Add HelpProvider on the form.
2. Add RadButton(or any other RadControl).
3. Use the following code:
this.helpProvider1.SetHelpString(this.radButton1, "RadButton help message.");
this.MaximizeBox = false;
this.MinimizeBox = false;
this.HelpButton = true;
4. Run the form, click form's help button and then click the button. - Help dialog is shown and instantly closed.

Workaround:
Subscribe to the control's HelpRequested event and show a tooltip.
this.helpProvider1.SetShowHelp(this.radButton1, false);
this.radButton1.HelpRequested += Control_HelpRequested;

private void Control_HelpRequested(object sender, HelpEventArgs hlpevent)
{
    Control control = sender as Control;
    if (control == null)
    {
        return;
    }

    hlpevent.Handled = true;
    RadToolTip tip = new RadToolTip();
    tip.Show(this.helpProvider1.GetHelpString(control), 3000);
}

How to reproduce: check the attached screenshot

Workaround create a custom RadPrintPreviewDialog
public class MyRadPrintPreviewDialog : RadPrintPreviewDialog
{
    protected override WatermarkPreviewDialog CreateWatermarkDialog()
    {
        WatermarkPreviewDialog dialog = new WatermarkPreviewDialog(this.Document);

        RadPageViewPage pageText = (RadPageViewPage)dialog.Controls["radPageView1"].Controls["pageText"];
        ((PlusMinusEditor)pageText.Controls["plusMinusEditorTextHOffset"]).TextBox.Width = 43;
        ((PlusMinusEditor)pageText.Controls["plusMinusEditorTextVOffset"]).TextBox.Width = 43;
        ((PlusMinusEditor)pageText.Controls["plusMinusEditorTextAngle"]).TextBox.Width = 43;
        ((PlusMinusEditor)pageText.Controls["plusMinusEditorTextOpacity"]).TextBox.Width = 43;
        RadPageViewPage pagePicture = (RadPageViewPage)dialog.Controls["radPageView1"].Controls["pagePicture"];
        ((PlusMinusEditor)pagePicture.Controls["plusMinusEditorImageHOffset"]).TextBox.Width = 43;
        ((PlusMinusEditor)pagePicture.Controls["plusMinusEditorImageVOffset"]).TextBox.Width = 43;
        ((PlusMinusEditor)pagePicture.Controls["plusMinusEditorImageOpacity"]).TextBox.Width = 43;

        return dialog;
    }
}

To reproduce: if you set in the app.manifest file  <dpiAware>false</dpiAware>, the controls still scale when changing DPI.

Workaround:
Public Class RadForm1
    Protected Overrides Sub OnLoad(e As EventArgs)

        Dim allowTheming = DirectCast(GetType(RadForm).GetField("allowTheming", BindingFlags.Instance Or BindingFlags.NonPublic).GetValue(Me), Boolean?)

        Dim behavior As ThemedFormBehavior = TryCast(Me.FormBehavior, ThemedFormBehavior)
        If behavior IsNot Nothing AndAlso allowTheming.HasValue AndAlso behavior.AllowTheming <> Me.AllowTheming Then
            behavior.AllowTheming = allowTheming.Value
        End If

        If Me.IsDesignMode Then
            GetType(RadFormControlBase).GetField("initialFormLocation", BindingFlags.Instance Or BindingFlags.NonPublic).SetValue(Me, Me.Location)

            Return
        End If

        Dim mi As MethodInfo = GetType(Form).GetMethod("OnLoad", BindingFlags.Instance Or BindingFlags.NonPublic)
        Dim ptr As IntPtr = mi.MethodHandle.GetFunctionPointer()
        Dim formOnOnLoad As Action(Of EventArgs) = DirectCast(Activator.CreateInstance(GetType(Action(Of EventArgs)), Me, ptr), Action(Of EventArgs))

        formOnOnLoad(e)
    End Sub

End Class

A pipeline control that have multi stage. Can dynamically add button (stage) to the stage list. Each stage can have two caption (Text) properties to display stage name and item in stage. Each stage also have onclick trigger.

Currently all the relevant methods, properties and classes are marked as internal. Expose the following:

In ComponentBehavior - ScreenPresenter, ShowScreenTip;

and the class ScreenTipPresenter.

Note that more methods, properties or classes may be exposed in the process of investigation.

Add radial menu like the one in the Telerik UI for Windows 8 XAML.

To reproduce:
Create a RadRibbonForm and using UI Spy move over the Close, Minimize or Maximize buttons. You will notice that the buttons cannot be selected since they do not have accessibility objects.

Currently the data cells of the grid are accessible, but the header cells are not. Expose the header cells.

Events like MouseUp, MouseLeave, MouseEnter, etc. should be available at design time.

Provide Grid's event similar to CellFormatting event which allows users to set the Cell Accessible Properties