I'm confused by this. I'm guessing either

A) he's adjacent to an opposing character- takes the action to make a close attack- before he does- he can move three away and the attack is still legal even though they are no longer adjacent.

Or

B) from three squares away can take a close action to make a close attack, but before he does so can move adjacent to a character in hindering and make the attack (that wasn't legal at the time it was declared due to lack of adjacency).

Also I'm guessing he couldn't use his smoke cloud and place himself in one of his three markers in the same turn, but could use smoke cloud and before placing his terrain pop over into a square of printed hindering.

He must be adjacent when he actually makes the attack. Nothing in the description alters the normal adjacency requirements.

Assign action, place adjacent, then attack. This is no different than other effects that have done similar things.

The hindering terrain would need to be there prior to the action, yes. So his Smoke Cloud would not really be usable with this effect.

If he had martial artist keyword he could be paired with the rare Michaelangelo from shredders return and go to town with the free action smoke cloud and side step.. it's almost as good as Taserface having a blaster and no range. Maybe they both will be errated?

Characters do not need to share keywords to be in the same team. There is nothing here to errata.

Agreed. Important to note further that errata should not be expected for min/max purposes. Hell, we don't even get errata so a piece just works, some times.

I cant help but feel the wording is just to restrict the placement to be before a costed action, not actually paired with it