Read this before playing! Endo-Evil is beside you. Press left arrow to turn to him if you hear him breathing. wait for a very short moment (About 2 seconds) before using the f key to flash them. Press up arrow to turn back to the front. Endo-Headless is over on the monitor. Press right arrow to view the monitor. If static is on it, you only have a short time to stop Endo-Headless. Hold down 1 while viewing the screen to prevent this, and wait until the screen shows Endo-Headless. The last, and most unique endo is SpringLock-Endo. He is sat at the front, you just need to click the springlock wind-up button at top left, to prevent it from entering 'animatronic' mode. (Found out it Doesn't actually work currently, so it is just there as a prop for now.) Survive for 3 Minutes to win!
Again, Scott is the best! Full game is here. You now have the choice of easy mode, or hard mode.