Today we have released an update to ACARS. It will update itself automatically next time you launch the program. After doing some extensive research we have finally got the Majestic Q400 to work flawlessly with ACARS. So you no longer need to press the Off/On Blocks buttons.
So from here onwards, select your flight, launch FSX (at the gate, with the engines off, and park brake set) and then start ACARS logging and start flying! ACARS will then automatically work out when you start your engines and then shut them down at the end of the flight.
We have also updated the flight code, so we wont get anymore duplicates and have to manually separate the flights!