So I had debated on whether or not to add one additional pic initially, but I just edited this post and added it in. This will show you something that you can't see from the back view of my sub, which should help you figure things out a bit more. It doesn't exactly spell it out (what fun would that be?), and still requires a bit of creative, devious thinking, but it should definitely help if you look at something (the same type of object) that is visible in pic 1, pic 5, and now also in pic 6 if you look closely...and now you can see the method of collecting the items too. Also, once you figure that part out...if you think about it a bit, it should help you figure out why the chains were scatter around the floor and the reason I placed the object where I did in pic 6.