I just used cheat engine because it was saying inventory full so I could only have 30 rifle bullets at a time. Not sure about day to night though because yeah it's pretty dumb. Eyeballs adjust to light/dark, but for some reason game devs insist on turning off game engines' automatic eyeball light level adjustment. Edit... I forgot this is Unity, not Unreal; not sure if it has auto exposure by default.
Seems the correct order of implementation would have been to first add light sources (flashlight, torch, lightning) and then add day/night cycles.