c# vs 2008 inkcanvas SelectionChanging   

My application displays shapes on an inkcanvas that can be selected moved and 
resized using event  SelectionChanging="OnSelectionChanging"
this canvas is saved to an .xaml file

selectionchanging event works perfect on the on new inkcanvas, but when 
canvas is saved and  opened and displayed on screen the selection moves the 
shapes to xy co-ordinates 0,0 (locationInInkCanvas )
 Point locationInInkCanvas = element.TranslatePoint(new Point(0, 0), 
myinkcanvas);


 public void OnSelectionChanging(object sender, 
InkCanvasSelectionChangingEventArgs e)
        {
          on_change_inkcanvas( sender,  e);

        }



   public void on_change_inkcanvas(object sender, 
InkCanvasSelectionChangingEventArgs e)
    {
            ReadOnlyCollection<UIElement> elements = e.GetSelectedElements();
          
            foreach (UIElement element in elements)
            {

                // obtain actual location of element relative to InkCanvas

                Point locationInInkCanvas = element.TranslatePoint(new 
Point(0, 0), myinkcanvas);
               
                element.SetValue(InkCanvas.LeftProperty, 
locationInInkCanvas.X);

                element.SetValue(InkCanvas.TopProperty, 
locationInInkCanvas.Y);
             
                element.SetValue(TextBlock.ForegroundProperty, new 
SolidColorBrush(col));

            
                // un-set right/bottom properties

             //   element.SetValue(InkCanvas.RightProperty, double.NaN);

              //  element.SetValue(InkCanvas.BottomProperty, double.NaN);

               
                // re-translate any render transform

                Matrix matRender = element.RenderTransform.Value;

                matRender.Translate(-matRender.OffsetX, -matRender.OffsetY);

                element.RenderTransform = new MatrixTransform(matRender);

                // set margins to zero

                if (element is FrameworkElement)
                {

                   ((FrameworkElement)element).Margin = new Thickness(0d);

                }

            }
        }


        public struct User_Var


Save canvas to .xaml file
  xamlFile = new FileStream(canvas_fname, FileMode.Create, 
FileAccess.ReadWrite);
  currentFileName = canvas_fname;
                XamlWriter.Save(this.myinkcanvas, xamlFile);


Open Xaml file on to myinkcanvas
xamlFile = new FileStream(thecanvasname, FileMode.Open, 
FileAccess.ReadWrite);                  
                  XmlReader xmlReader = XmlReader.Create(xamlFile);
                   InkCanvas myinkcanvas = 
(InkCanvas)XamlReader.Load(xmlReader);
                    canvas_file_open = true;
                    myinkcanvas.SelectionChanging += new 
InkCanvasSelectionChangingEventHandler(on_change_inkcanvas);                  
  
                    WordScroll.Content = myinkcanvas;

date: Thu, 3 Apr 2008 14:33:01 -0700   author:   amitch