Is enabling 'HELP' button in MessageBox possible???

Hi. Though 'WinUser32.mqh' include references to the 'HELP' button, including its return code (9), clicking on it has no effect and no code is returned. IS there any way to get this working?

For the record, I have written a script with 3 options to BUY, SELL or reverse an already open position. However I need a fourth button to 'cancel' in case I change my mind. Clicking on the 'x' on the top corner of the window either returns a code (Cancel) or is greyed out (when using the MB_ABORTTRYIGNORE switch) which is silly...