How to serialize schema settings while using custom engine in WinForms GridGroupingControl?

public class CustomEngine: GridEngine 
{ 
    public override ChildTable CreateChildTable(Element parent) 
    { 
        return new GroupingChildTable (parent); 
    } 
   /// <summary>
   /// Creates a valid stream for custom engine
   /// </summary>
    public override GridEngine CreateFromXml(XmlReader xr) 
    { 
        XmlSerializer serializer = new XmlSerializer(typeof(CustomEngine)); 
        object obj = serializer.Deserialize(xr); 
        xr.Close(); 
        return obj as CustomEngine; 
    } 
 
    /// <summary>
    /// Saves the engine changes to an XML stream.
    /// </summary>
    public override void WriteXml(XmlWriter xw) 
    { 
        XmlSerializer serializer = new XmlSerializer(typeof(CustomEngine)); 
        serializer.Serialize(xw, this); 
    } 
}

Public Class CustomEngine
        Inherits GridEngine
        Public Overrides Function CreateChildTable(ByVal parent As Element) As ChildTable
                Return New GroupingChildTable(parent)
        End Function
        
        ''' <summary>
        ''' Creates a valid stream for custom engine
        ''' </summary>
        Public Overrides Function CreateFromXml(ByVal xr As XmlReader) As GridEngine
                Dim serializer As New XmlSerializer(GetType(CustomEngine))
                Dim obj As Object = serializer.Deserialize(xr)
                xr.Close()
                Return TryCast(obj, CustomEngine)
        End Function
 
        ''' <summary>
        ''' Saves the engine changes to an XML stream.
        ''' </summary>
        Public Overrides Sub WriteXml(ByVal xw As XmlWriter)
                Dim serializer As New XmlSerializer(GetType(CustomEngine))
                serializer.Serialize(xw, Me)
        End Sub
End Class