Quoted from sethi_i:
"Light is green...trap is clean." It doesn't have anything to do with the storage facility becoming more or less unstable. It's never unstable. It explodes when "dickless" turns off the power. Watch the clip. Open the door to insert trap....red light. Insert trap....green light. Turn power off...sirens. The progression (on both the DMD and the physical faciltiy) match the scene exactly.
I FEEL LIKE I'M TAKING CRAZY PILLS!!
You are not crazy. It is just the difference between the current state - which is an imprecise summery of the movie rule-set that no one really remembers exactly until they re-watch the video, and another imprecise summery of the movie rule set (that may arguably be based slightly more loosely on the movie) but is a more intuitive state. The fact is that the device changes from dangerous to safe to emergency in a way that seems incongruous with a 1st, 2nd, 3rd ball trigger, and the rationale isn't explained as well as it could be.
I would be equally happy if they used sound effects, text, or call outs to explain the logic of the 1st 2nd 3rd ball as well. For example, if they made it clear that 1st ball is ghost is loaded, 2nd ball is ghost is safely transferred, and 3rd ball is the shutdown of the containment field, (which to your point, is what I think they were aiming for, although then the red light should be turned off on the 2nd ball when the green light comes on) -- and all of that was actually obvious in-game -- then great!
But as it is now, you have an incremental progression of 1st, 2nd and 3rd balls with lights that go (1) red, (2) red-green, and finally (3) red-red. It looks weird and could have used an update explaining it better.