Hi guys, I cant seem to get this to work. I have read the manual, tried the forums and now I have to ask someone. I cant get the SaveToFile and LoadFromFile to work. I created a really simple app - but no luck. Could any one please point out whats wrong with this? It seems really simple, so its driving me mad. If there is no obvious mistake - the IDE raises a null exception on the LoadFrom(System.IO.BinaryReader reader, PersistContext ctx) function. Here is my code:

public class TestNode : ShapeNode
    {
        public TestNode()
            : base()
        {
        }

        protected override void SaveTo(System.IO.BinaryWriter writer, PersistContext ctx)
        {
            base.SaveTo(writer, ctx);
        }

        protected override void LoadFrom(System.IO.BinaryReader reader, PersistContext ctx)
        {
            base.LoadFrom(reader, ctx);
        }
    } 

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            Diagram.RegisterItemClass(typeof(TestNode), "TestNode", 1);

            TestNode test = new TestNode();
            diagram1.Nodes.Add(test);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            //A save button
            diagram1.SaveToFile("Test");
        }

        private void button2_Click(object sender, EventArgs e)
        {
            //A load button
            diagram1.LoadFromFile("Test");
        }
    } 

Ah ha, that would why then I changed it and it worked out fine. Thanks Stoyo!

oh - forgot to say that the control is a user control with a few buttons, a list view, a checkbox and is [serialized].