static extern NavStatus NavCustomControl(IntPtr dialog, NavCustomControlMessage selector, ref AEDesc parm);
static extern NavStatus NavCustomControl (IntPtr dialog, NavCustomControlMessage selector, ref AEDesc parm);
static extern NavStatus NavCustomControl(IntPtr dialog, NavCustomControlMessage selector, IntPtr parms);
static extern NavStatus NavCustomControl (IntPtr dialog, NavCustomControlMessage selector, IntPtr parms);