public enum DragMode : System.Enum 

private void CreateGcTrackBarWithExpectedDragBehavior()
{
    // Create a instance of GcTrackBar.
    GrapeCity.Win.Bars.GcTrackBar gcTrackBar1 = new GrapeCity.Win.Bars.GcTrackBar();

    // Initialize the Name, Location and Size of GcTrackBar
    gcTrackBar1.Name = "gcTrackBar1";
    gcTrackBar1.Location = new System.Drawing.Point(8, 8);
    gcTrackBar1.Size = new System.Drawing.Size(224, 45);
    gcTrackBar1.ThumbValueChanged += new EventHandler<ThumbValueChangedEventArgs>(gcTrackBar1_ThumbValueChanged);

    // Add the second Thumb to the Thumbs of GcTrackBar
    GrapeCity.Win.Bars.Thumb thumb1 = new GrapeCity.Win.Bars.Thumb();
    gcTrackBar1.Thumbs.Add(thumb1);

    // Set DragMode property to Trunk, two thumbs can't be covered and crossed together. 
    // When one thumb is next to other one,if try to the preceding thumb, the two thumbs will move together.
    gcTrackBar1.DragMode = DragMode.Trunk;
   
    // Set the delta value of thumb moving by mouse dragging
    gcTrackBar1.DragFrequency = 2;

    // Add gcTrackBar1 to the form
    this.Controls.Add(gcTrackBar1);
}

void gcTrackBar1_ThumbValueChanged(object sender, ThumbValueChangedEventArgs e)
{
    // Display the changed NewValaue of current selected Thumb in the text box.
    this.textBox1.Text = "" + e.NewValue;
}