For the credits part, you will need to use up the starting credits first before getting infinite credits. If you are starting with 5000, get yourself a double handgun or something then you'll see the change in your credits.
Would like to request an update for this trainer and added with 'infinite energy' cheat.
In some cases, the trainer can still be used. The infinite credit cheat doesn't seemed to work now. Besides that, there is some chances, it will cause the game to get bugged. I had encounter dino mobs that couldnt be killed while using it and in rare occassion in high difficulty games, the mobs can kill me even with the armor cheat on. Therefore, I hope there is an update and bug-fix to it.