**_Killer thriller, killer message_** A mob hit-man (Mickey Rourke) teams-up with a young psycho (Joseph Gordon-Levitt) and they go after a separated couple (Diane Lane & Thomas Jane) who witnessed a botched hit. Rosario Dawson is on hand as the twerp's girlfriend. "Killshot" (2008) is a thriller/drama by John Madden that supposedly had post-production problems, sat on a shelf, was reedited and whatever else. As such, some criticize that it doesn't flow well. Don't believe it. This is a very professionally-made film and I never got the sense that the story didn't flow, regardless of what…