I have the current trainer, and have found one bug that comes up with it. Was playing the first mission as Trevor where you go and shoot up the trailer park, with the health active the Lost MC targets also get invulnerable. Ya shoot them and they'll fall down but then get back up afterwards. Only had this bug while dealing with Lost members as it also happened playing Franklin and helping the guy look for his niece hanging with Lost guys down at the end of the docks.
Might want to check the coding somewhere about it, I have the Steam version 331 and 124 as shown in the GTA V loading screen. Other than that it's a great trainer.
I had no problem finishing this one with health = num 1 on.
I suppose you had num 8 = no fall damage on, this makes npcs invulnerable. Do not turn this option on during missions.
how to download
Go here Link and click download next to the trainer. It's as simple as that. The trainer is right near the top there. It's the only one other then the saved game.