Run the game without EasyAntiCheat (just run 7DaysToDie.exe file). Run trainer. Trainer should say that it found a game. Then begin the game. Then you can activate health function. If you want to activate ammo/resources/degradation functions then you must first decrease them (like shoot arrows, upgrade something using resources, use tool to degrade it a little). Before function is activated trainer will search for code signature. It may take some time. If not found it will say.
Trainer is based on Alpha 16.4 (b8) version of the game.