Hi Roland,

You cannot check for multiple keypresses with a single operation.  In the
Keys enumeration, letter keys do not have "Flag" values that can be OR'd
together, such as Keys.N | Keys.P.  In this case, Keys.N = 78 and Keys.P =
80.  Only the modifier keys such as Keys.Shift can be OR'd with letter keys,
such as Keys.Shift | Keys.N.

Instead, to detect a complex key sequence, you need to save the state of the
keypress then check that state on the next keypress.  For example:

private Keys m_PreviousKey;
private void MdiParentForm_KeyDown(object sender, KeyEventArgs e)
{
    switch(e.KeyData)
    {
        case Keys.Control|Keys.N:
            Console.WriteLine( "First key" );
            break;
        case Keys.P:
            if (this.m_PreviousKey == Keys.Control|Keys.N)
                Console.WriteLine( "GOT IT!" );
            break;
    }
    this.m_PreviousKey = e.KeyData;
}