The mouse dragging can take a bit to get use to but I kind of knew the game needed to have players look away from the suitcase other wise they'd do nothing but stare at it haha. Maybe it is because I know the exact timings, but the suitcase can swing open pretty wide before a game over. It takes about 15 to 20 seconds for the case to lead to a game over, there is a small audio cue as well (latch thudding noise) meaning the case is fully open and you have a few extra seconds to shut it before it ends. There is some slightly random chance as well but more so to help the player such as the Widow checking for a larger amount of times the suitcase was shut rather than the minimum. Generally if you watch how far the case opens before it ends you can see it opens in increments which can help judge when you should shut it. Hope that helps if you want to go back (or anyone else!)