Sure, no problem. In fact it's not the code I use (we write in VB), it's a slightly modified version of the code from the link you provided. Clipboard class is in the System.Windows.Forms namespace and Bitmap is from System.Drawing.
RenderList list = new RenderList();
//Create render list, add only the shapes you want
foreach (Shape shape in flowchart1.Shapes.Values)
{
list.Add(shape);
}
foreach (Line line in flowchart1.Lines.Values)
{
list.Add(line);
}
//Sort for correct zorder
list.Sort();
//Save existing render rectangle
Rectangle rect = flowchart1.Render.RenderRectangle;
//Set up renderer for output render
flowchart1.RenderDesign.DrawGrid = false;
flowchart1.Render.Elements = list;
flowchart1.Render.RenderDiagram(new Rectangle(new Point(0, 0), flowchart1.DiagramSize));
Bitmap bmp = new Bitmap(flowchart1.Render.Bitmap);
//Reset render
flowchart1.RenderDesign.DrawGrid = true;
flowchart1.Render.RenderDiagram(rect);
flowchart1.Refresh();
// copy image to the clipboard in .NET 2.0
Clipboard.SetImage(bmp);
// .NET 1.x
Clipboard.SetDataObject(bmp, true);