Latest posts I see are approximately a week old, just picked up Parklife loaded a new game started the trainer as usual hit F1 for infinite money and get a windows ding instead of the "Trainer Activated" have attempted to play after the ding and no update to in game cash as time goes by. Looks like there may have been an update that breaks the trainer, and yes F1 is the infinite money option the others are saying still works but does not for me.
*For some reason after deleting old 1.9 trainer and downloading again the trainer is working with infinite money again, if anyone else is having issues with the trainer not working with the new expansion maybe try this as well, did work for me once this was done.