non client area buttons (maximize, minimize, close) do not glow

I have a very simple c# program, but the top-right 3 buttons don't show any animation when I hover the mouse over them.

My code its made for flicker free

The main form is MDI Parent with this

protected override CreateParams CreateParams
    {
        get
        {
            CreateParams cp = base.CreateParams;
            cp.ExStyle |= API.WS_EX_COMPOSITED;  // Turn on WS_EX_COMPOSITED
            return cp;
        }
    }

The result... the child mdi forms don't show any animation when I hover the mouse over the top-right 3 buttons (close, maximize, minimize).