Who builds all the traps.does he have a construction crew on hand? Like the one at the shopping mallhow could he get all the stuff There w out being seen? And how come the traps all work perfect? Nothing works perfect in real life

Yeah, the idea was that Kerry wasn't supposed to escape. As Hoffman said, "It was designed for her execution". I think that it was Jigsaw who recorded the tape, but I think we are to presume that Amanda changed the trap a bit afterwards..?
But there's another thing that gets me. If the device was hooked into/under Kerry's ribs, then why when it went off didn't it open up her chest? All we see is a layer of muscle. Her lungs and heart would have been exposed. Our ribs are under our muscles, not over it lol.

Well jigsaw definitely recorded the tape, and he defintly had a design as if you look in the background you can see blueprint drawings. My guess is that the original design the harness not only unlocked the bolt but it unlocked a mechacgnism which bring the connections out of the ribs and so allow her to push it of and get down
Pointing me out on spelling is just one hell of a poor argument..

Maybe if the actual key unlocked it , it could be painfully pulled out. It may have been designed to not cause fatal punctures like the rods trap later in the series.

I assumed Amanda used some sort of voice-changer or something and recorded the tape herself.
The Emperor is not here.
I
speak for the Empire.

But Jigsaw provided the narration for her tape, which means he knew about the Angel trap since he describes how to get out of it. If it was always designed to be inescapable he would have stopped her from doing it.
Ram this in your clambake, bitchcakes!

I think that's the point. I have to imagine that Amanda designed it herself so there was never any way for Detective Kerry to actually free herself.