Saw (2004)

Answer: Amanda was supposed to put the key around Adam's neck rather than just on his chest. If she had done so as instructed by Jigsaw, he would've been able to unlock his shackle and leave the bathroom. Adam was a voyeur, the irony being that if his key had been placed correctly around his neck, all he would've had to do would be to look around to find it. Adam's tape states, "what do voyeurs see when they look into the mirror, " so, again, it's a hint that all Adam would've had to do was look at himself. I noticed as well, Jigsaw says, "the key to that chain is in the bathtub." /IS/ in the bathtub. Not /was/. So Jigsaw probably thought Adam could still get out. He says, "so many people are ungrateful to be alive. But not you. Not anymore." So it's like, 'I have taught you this lesson, now you can go free because now you'll appreciate your life unlike you did before'.

Answer: It's mentioned multiple times throughout the movie how unambitious and apathetic Adam is, and how angry he is at the world. His game is to actually escape, which he fails because he's quite content to let Dr. Gordon go and get help instead of trying to do something himself. He was meant to be able to roam freely around the room, and that would probably have made his and Dr. Gordon's relationship and interactions a lot more severe and hostile. The reality of it is simple: Saw is a rushed movie. It's fun to speculate and theorize, but the truth is that by the time they got to editing, they had already lost a chunk of footage after only having 18 days to shoot.

Answer: Adam simply had to either unlock his chain with the key, if it hadn't gone down the drain, or cut his foot off to get out. Or he could've pulled an Eric Matthews with the toilet lid and try to get out that way, but that idea wasn't introduced until Saw III. Let's say Lawrence killed Adam before 6AM. Lawrence would win his game, yes. But he's missing a foot, and the door is still locked because Zep or someone would have to unlock it still. But would Zep or John have to help Dr. Gordon and provide medical attention? Ignore Saw 3D for a second and focusing solely on the first film, I'd say I don't think either of them would do so. Lawrence would be left to get help for himself. Imagine if Mark or Paul beat their tests. Would Jigsaw get them help? He didn't try to help Amanda. He let Amanda fetch help for herself. This also shows that Dr. Gordon was supposed to have died at the end of the first film.