// NOTE - You can't just add an OnShapeDoubleClick handler to a shadow and get the event
        // You also need to change the shapesheet (in .vss file and in upgrade) to use the
        // double click handler used by others "RUNADDONWARGS(\"QueueMarkerEvent\",\"/PathMaker /CMD=1\")"
        private void OnShapeDoubleClick(Shape shape)
        {
            Shadow shadow = LookupShadowByShape(shape);

            if (shadow != null)
            {
                shadow.OnShapeDoubleClick();
            }
            else
            {
                Common.ErrorMessage("Error - double clicking on unexpected item " + shape.Name);
            }
        }