Terrific movie!

Wow, this is a really hard-core time-travel movie. It seemed to be trying to outdo Primer and I think it succeeded! I admit that I lost track by the ending. Has anyone done a diagram of all the time-travel instances depicted (or implied) in the film? I guess I should wait for the DVD so I can rewatch it, and rewind etc., but it was nice to see on the big screen with an audience (there were more laughs in the last third of the film than the first two-thirds).

Some things I'm not sure of; I'll put this all in spoiler tags:

1. Lana wasn't really in an infinite loop, was she? There was a point where it appeared that the "wrong Lana" had gone back in time, and Dean believed that she was in an infinite loop, just going back every year (he drew a diagram of it) but that wouldn't make any sense, right, because she'd get noticeably older.

2. The business with the "open loop" and "closed loop", Dean thought that by tightening a screw or something he could change it from closed to open, right? Was he correct about that?

3. How many times does Dean travel back in time? Five? Six?

4. We see Dean's hand get injured in the car window; does he ever make it to the hospital? I was looking for a permanent remnant of that injury, in later scenes, but after that his hand seemed normal.