I've just downloaded, looked fun to play, it bugged for me at the bathroom scene, all went black, couldn't move the lighter was buggy and kept going on and off. Restarted the game, but still the same. Sad about that as I would like to have seen the end :(
Is it cause you falling through the map I wonder? I have seen that a few times before on other videos. If the player steps on the toilet rolls they can go through the wall in the bathroom! Anyway if you decide to try again. You don't need to go to the bathroom at all to progress. Its just a jumpscare scene thingie :)
Also a simple pushing of F once should turn the lighter on and off. Maybe there is a slight delay with animations, but one push should do it.