I have a routine for the OnMouseWheelUp event, but it doesn't seem to get fired on when using Google Maps. Using the wheel does zoom in and out, but the event doesn't do anything.

In code, I do this:

But, this event never gets fired:

procedure TFTMSMap.FNCGoogleMapsMouseWheelUp(Sender: TObject;
Shift: TShiftState; MousePos: TPoint; var Handled: Boolean);
TraceMsg('Wheel Up');

Is there a different event to use?

OnMouseWheelUp is not fired because the browser internally consumes the events. You need to use the map specific events. Unfortunately there is no event exposed to use the OnMouseWheelUp. We'll investigate the possibilities.