Please use the project attached.

1.Run the application with multi-monitor configuration.
2.Undock toolWindow1 from RadForm1 and maximize it to the different window.
3.Close the application (the layout will be saved).
4.Run the application again.

Workaround: handle the FloatingWindowCreated event and set FormWindowState.Maximized for the floating window.


    protected override void OnLoad(EventArgs e)
    {
      base.OnLoad(e);
        this.radDock1.FloatingWindowCreated+=radDock1_FloatingWindowCreated;
      if (File.Exists(FileName))
        radDock1.LoadFromXml(FileName);
    }

    private void radDock1_FloatingWindowCreated(object sender, Telerik.WinControls.UI.Docking.FloatingWindowEventArgs e)
    {
        e.Window.WindowState = FormWindowState.Maximized;
    }