Last chapter a little confusing: help!

Well, this isn't the most eventful board, but I'll ask anyway. I really enjoyed this serial, but a few things are unclear during the last chapter:

1) Obviously, Atom Man and Lex are one in the same (didn't have to look at the cast list on imdb either), but the identity just seemed to drop out of the picture. There was no unmasking moment or answer to the mystery at all (maybe I missed it, as I watched in a few sittings and got a little board near the end, but I doubt it.)

2) Lex's plan to send Earth quakes throughout the globe is abandoned as soon as Superman shows up? Did he have a way to do it from the ship (he talked about having a version of his lab up there.) Why didn't he program more before he left? I ask b/c it does not seem like the machine was destroyed when he sent quakes nearby harming the hideout, nor did Superman smash it when he arrived.

3) Ok, at the end (SPOILER) why was Superman so hot to get Lex back to Earth and jail, yet left the 2 henchmen to go out in space? Moment later a meteor or something hits it and kills them. Superman does not kill and would have know a meteor was coming due to his super hearing. So even if he was letting them get off scott-free, he wouldn't have let them die.

4) The end of the movie does not explain any of these things nor does any character seem concerned.

Am I unreal? Am I a character who can’t possibly exist? – Alissa Rosenbaum