Activating this trainer:

Press F1 at main menu.

Listen for 'Trainer Activated'.

Press desired hotkey. All hotkeys can be changed on the trainer.

Trainer Options:

Numpad 1: Unlimited Health
Numpad 2: Unlimited Stamina
Numpad 3: Unlimited Ammo
Numpad 4: No Reload
Numpad 5: Teleport Boss Cannot Attack
Numpad 6: Multiheaded Boss Cannot Attack
Numpad 7: Stupid Lesser Zombies
Numpad 8: Easy Craft Items
Numpad 9: Easy Craft Weapon Upgrades Weapon Parts
Numpad 0: Easy Craft Weapon Upgrades High Grade Parts
Numpad /: Easy Upgrade Character Green Gel
Numpad *: Easy Upgrade Character Red Gel
Numpad -: Super Score Gallery Mode Shooting Game
Numpad +: Super Score Chain Attack Shooting Game
Numpad .: Unlimited Locker Keys

Notes:

Numpad 1: Unlimited Health - toggle on and during combat, this will attempt to keep your health at 100%.  This does not protect you from scripted deaths or single shot kills that are designed to kill you.

Numpad 2: Unlimited Stamina - toggle on and you have unlimited stamina to run and etc.

Numpad 3: Unlimited Ammo - toggle on and when you reload, if you have ammo it will be at max.

Numpad 4: No Reload - toggle on and when you fire, most weapons will not need to be reloaded.

Numpad 5: Teleport Boss Cannot Attack - there is a protagonist in the game who appears at times and may attack you if you are seen. If you keep failing the stealth portion of the game in those instances, toggle this on to get past the boss, then toggle back off when done.

Numpad 6: Multiheaded Boss Cannot Attack - there is a multiheaded boss in chapter 2 that crashes through the window and may be difficult for some.  Toggle this on and that boss (even when it appears later) generally will stand still.  May work on other bosses, but it appears this game coded each major AI with separate code.

Numpad 7: Stupid Lesser Zombies - this makes most of the zombies scattered through the city ignore you or act erratically. This will save you a lot of time and aggravation as you are searching and moving about.  May not work on specific scripted events or special zombies that are part of the story, etc.

Numpad 8: Easy Craft Items - at the crafting stations, toggle this on once you are in the station, and then select the item you wish to craft.  Even if you are missing the parts, you can likely craft the item.  If the blueprint is showing a part that you NEVER COLLECTED, then it's best to not craft those yet, as they are unlocked when the story gives them to you.

Numpad 9: Easy Craft Weapon Upgrades Weapon Parts - at the crafting stations, toggle this on once you are in the station, and then select the item you wish to upgrade.  Even if you are missing the parts, you can likely upgrade the item.  If the blueprint is showing a part that you NEVER COLLECTED, then it's best to not craft those yet, as they are unlocked when the story gives them to you.

Numpad 0: Easy Craft Weapon Upgrades High Grade Parts - at the crafting stations, toggle this on once you are in the station, and then select the item you wish to upgrade.  Even if you are missing the parts, you can likely upgrade the item.  If the blueprint is showing a part that you NEVER COLLECTED, then it's best to not craft those yet, as they are unlocked when the story gives them to you.

Numpad /: Easy Upgrade Character Green Gel - at the upgrade chair where you can upgrade your character stats and power, toggle this on and then you can upgrade the character even if you have none of the gel.  If you have not collected this color gel, it's best to not do this yet, as you may crash the game.

Numpad *: Easy Upgrade Character Red Gel - at the upgrade chair where you can upgrade your character stats and power, toggle this on and then you can upgrade the character even if you have none of the gel.  If you have not collected this color gel, it's best to not do this yet, as you may crash the game.

Numpad -: Super Score Gallery Mode Shooting Game - toggle this on and then when you strike a target, you will have 100000 points.

Numpad +: Super Score Chain Attack Shooting Game - toggle this on and then when you shoot at a target that starts a chain, you will have at least 500000 points.

Numpad .: Unlimited Locker Keys - you must have at least ONE Locker Key. Go to the treatment room, click on the Locker area but DO NOT choose a locker yet.  Toggle the option on, THEN click on a locker.  You will not lose a key.  Repeat until you are finished then make sure to TOGGLE THE OPTION BACK OFF before leaving the treatment room.