Most of your problems are know/ have already been taken care of in newer versions of the game.This has promise. Here's the problems I encountered in verson 0.6:
The gun modding menu needs some work, most of the drop down boxes are nearly invisible, with some of them being off the screen. The lower reciever is almost entirely covered up by the magazine.
When a button prompt appears, like the struggle button, I first have to make the mouse appear, before I can even click it.
The flashlight button does not appear to work outside of the tutorial.
The reason why you can not turn of the flashlight is probably because you have a scrap flashlight, which is always on. Search for a modern/ composite one or remove it from the gun to turn it of.