Activating this trainer:

If not state otherwise below, press F1 at main menu.
Listen for 'Trainer Activated'.
Press desired hotkey. All hotkeys can be changed on the trainer.

Promo Options:

Game: Total Time Played in Game

Trainer Options:

NumPad1: Unlimited HP
NumPad2: Unlimited SP
NumPad3: Weak Enemies
NumPad4: Instant Win Battles
NumPad5: Unlimited Skillpoints

Editor Options:

Player Stats: Total XP (Stats Menu)
Player Stats: Stress (Stats Menu)
Player Skills: Skill Points (Skill Menu)
Game: Total Time Played in Game

Notes:

EDITOR OPTIONS
For Player Stats, press ESC to open the Main Menu, then click on Status, then note the values are present.  You can then modify the values and press TAB to lock them in.  Note that almost everything that is in progression, including your HP and SP and Level, are tied directly to your XP.  So if you give yourself a lot of XP, then SAVE, then LOAD, you will see that your character will have higher stats of everything.  Note that if you have high XP/Level, that some creatures in the game you cannot attack or won't attack you due to the discrepancy of power.

For Player Skills, press ESC to open the Main Menu, then click on Skill, then note the value present.  You can then modify the values and press TAB to lock it in.

For Game Time, press ESC to open the Main Menu, then note the value present.  You can set the value higher or lower to modify the time, then press TAB to lock it in.

Unlimited HP:
Toggle on and the trainer tries to keep your health full.

Unlimited SP:
Toggle on and the trainer tries to keep your SP full.

Weak Enemies:
Toggle on and when it's the enemy turn, their health and SP are low.

Instant Win Battles:
Toggle on and if left on, the battle is instantly over and you win.

Unlimited Skillpoints:
If you have Skillpoints and can spend them, when you spend them they don't decrease.