I am having problems adding data to the UltraTree when the view style is in outlook express.  I think the problem is that I am not quite sure how to use the UltraTreeColumnSet.  Are there examples in adding data to the ultra tree?

Below is a snippet of my code, the error occurs in the bold line where I am setting the cell value for a child node.  I am able to set the cell  value of the parent node, but I get an error for the child node.  I get a runtime error "Object reference not set to an instance of an object"

 DataTable dataTable = InitializeTable();

            UltraTreeColumnSet rootColumnSet = InitializeColumnSet();

            ultraTree.Nodes.Clear();

            UltraTreeNode rootNode = ultraTree.Nodes.Add(id+ "_" + index);
            rootNode.Text = id;
            rootNode.SetCellValue(rootColumnSet.Columns["Id"],id);
            rootNode.SetCellValue(rootColumnSet.Columns["Description"], "description");
            rootNode.SetCellValue(rootColumnSet.Columns["EU"], "EU");

            UltraTreeNode childNode = new UltraTreeNode("childNode");

            try
            {
                childNode.Text = "hello";
                childNode.SetCellValue(rootColumnSet.Columns["Id"], "hello");
                childNode.SetCellValue(rootColumnSet.Columns["Description"], "desc");
                childNode.SetCellValue(rootColumnSet.Columns["EU"], "eu");
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message);
            }

            rootNode.Nodes.Add(childNode);

private UltraTreeColumnSet InitializeColumnSet()
        {
            DataTable dataTable = InitializeTable();

            UltraTreeColumnSet rootColumnSet = ultraTree.ColumnSettings.RootColumnSet;

            foreach (DataColumn dataColumn in dataTable.Columns)
            {
                UltraTreeNodeColumn column = rootColumnSet.Columns.Add(dataColumn.ColumnName);

                column.DataType = dataColumn.DataType;
            }


            return rootColumnSet;
        }

        private DataTable InitializeTable()
        {
           //    Create a DataTable
           DataTable dataTable = new DataTable();

           //    Add some columns
           dataTable.Columns.Add( "Id", typeof(string) );
           dataTable.Columns.Add( "Description", typeof(string) );
           dataTable.Columns.Add( "EU", typeof(string) );
          
           return dataTable;
        }

Any help is appreciated!!

 Jaime