Hey thanks for playing and we are glad that you enjoyed it! If it is not too much trouble we would really appreciate a few more details or maybe even a screenshot of the specific place where you are finding this issue? I have been unable to reproduce it myself and your insight would be very helpful. One possible reason for the guard being alerted could be that the box was pushed over one of the glass tiles? Whenever you step on glass or push a box over it, the guards will hear you and are immediately alerted.