using GrapeCity.ActiveReports.Document.Section.Annotations;

private void AddAnnotations()
{
    rptAnno rpt = new rptAnno();
    rpt.Run();
    this.viewer1.Document = rpt.Document;

    AnnotationLine line = new AnnotationLine();
    line.ArrowCapWidth = 4.5f;
    line.ArrowCapHeight = 4.5f;
    line.DashStyle = System.Drawing.Drawing2D.DashStyle.DashDotDot;
    line.DashCap = System.Drawing.Drawing2D.DashCap.Round;
    line.ShowArrowCaps = AnnotationLine.ShowArrowCap.RightOnly;
    line.FillArrowCaps = true;
    line.LineColor = Color.Red;
    line.LineWidth = 1;
    line.LineLocation = AnnotationLine.LinePlacement.Bottom;
    line.Text = "Please review.";
    line.TextColor = Color.Blue;
    line.TextAlignment = System.Drawing.StringAlignment.Center;
            
    line.Attach(4, 4);
    this.viewer1.Document.Pages[0].Annotations.Add(line);

    line.Height = 0.50f;
    line.Width = 1.5f;
}