No I mean a movie to explain:
1 why MIB was kept in a cabin,
2what ash has to do with him,
They figured out that ashes from a burned [who knows?] would stop him. We saw it stop the smoke when it was burnt Jacob. Maybe the ashes of a burnt candidate or whatever will work.
Either way, someone tricked Smokey into going into the cabin, then trapped him with the ash. Or, Jacob surrounded himself or another candidate with ash to keep Smokey out.
3what is this game they are playing,
4what are the rules,
The battle for the redemption of mankind. If Jacob finds a successor who meets criteria, he wins. If Smokey rules out all candidates, he wins.
The rules are, Smokey can't directly harm any candidate. He either has someone else do it, or he convinces them to forfeit. Smokey can read minds and take the form of any dead person.
Jacob's self-imposed rule is that he doesn't directly tell a candidate what to do.
5 is MIB still part of smokey or did smokey take MIB over,
Looks like Smokey is what's left of MiB, although (less likely) the body just released a separate entity from the cave.
6why Jacob wants to prove to MIB that people are good when his whole life his mother said they weren't and he was to stay away from them,
Mother wanted MiB to be The One. That's probably why he had the magic powers even as a boy (saw dead mom). Mother wanted him to carry on in the tradition of distrusting the nature of man. She fed him the line "they come, they fight, etc...it all ends the same"
Jacob accepted the default, 2nd choice appointment as Protector, but he didn't share his step-mom's pessimism. He's out to prove her wrong. See 3 and 4 above.
7etc etc etc...
basically all the key info we should have gotten last night but didn't
Sure, what I wrote (as if it's gospel) is combined speculation and established fact. I recognize your frustration with not having been given crystal-clear exposition of every last element. Not only is it best to leave some things for the viewer to work out, also keep in mind that we have another episode PLUS a movie that's as long as Avatar to finish clarifying things.