When you reach the orange box, the controls change, as it is meant to be a trap the silencers have left for you. I understand it is not the most intuitive in the end however but I was rushing to implement it before the deadline. The end of the level is when you reach the green win screen. (At the end of the orange box). The changed controls can be found on the help screen (from the main menu). But to move left becomes "C", and to move right is "V".