If you wish to use Ctrl+Tab key to move through the document dock tabs on active Bar control add following code to your form to enable that:

C#

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
    // Detect the keys pressed and ensure that there is an active control
 
    if ((keyData & Keys.Tab) == Keys.Tab && (keyData & Keys.Control) == Keys.Control && this.ActiveControl!=null)
    {
        // From active control try to find the Bar control
 
        Bar bar = GetActiveBar();
 
        // Ensure that Bar is the document bar
 
        if (bar != null && bar.DockSide == eDockSide.Document)
        {
            // Cycle throught the DockContainerItem controls on the bar...
 
            if (bar.SelectedDockTab + 1 < bar.Items.Count)
                bar.SelectedDockTab++;
            else
                bar.SelectedDockTab = 0;
 
            // Notify system that we handled the message so the Tab key does not end up in control with focus
 
            return true;
        }
    }
 
    return base.ProcessCmdKey(ref msg, keyData);
}
 
// Goes through the parent chain of active control in attempt to find the Bar control
 
private Bar GetActiveBar()
{
    Control c = this.ActiveControl;
 
    while (c != null && !(c is Bar))
        c = c.Parent;
 
    return c as Bar;
}

VB

Protected Overrides Function ProcessCmdKey(ByRef msg As System.Windows.Forms.Message, ByVal keyData As System.Windows.Forms.Keys) As Boolean
    ' Detect the keys pressed and ensure that there is an active control
 
        If (keyData And Keys.Tab) = Keys.Tab And (keyData And Keys.Control) = Keys.Control And Not Me.ActiveControl Is Nothing Then
            ' From active control try to find the Bar control
 
            Dim b As DevComponents.DotNetBar.Bar = GetActiveBar()
 
            ' Ensure that Bar is the document bar
 
            If Not b Is Nothing AndAlso b.DockSide = DevComponents.DotNetBar.eDockSide.Document Then
                ' Cycle throught the DockContainerItem controls on the bar...
 
                If b.SelectedDockTab + 1 < b.Items.Count Then
                    b.SelectedDockTab = b.SelectedDockTab + 1
                Else
                    b.SelectedDockTab = 0
                End If
 
                ' Notify system that we handled the message so the Tab key does not end up in control with focus
 
                Return True
 
            End If
        End If
 
    Return MyBase.ProcessCmdKey(msg, keyData)
 
End Function
 
' Goes through the parent chain of active control in attempt to find the Bar control
 
Private Function GetActiveBar() As DevComponents.DotNetBar.Bar
    Dim c As Control = Me.ActiveControl
 
    While Not c Is Nothing AndAlso Not TypeOf (c) Is DevComponents.DotNetBar.Bar
        c = c.Parent
    End While
 
    Return CType(c, DevComponents.DotNetBar.Bar)
 
End Function