In both cases, there is a problem.
In 64 bit, all up column of smoke. (Big issue when you are far enough away)
In 32 bit, down column of smoke. (Small issue when you are far enough away, but very weird when you're close)
This issues are obvious and they're in the game from the beginning (even if it's worse since 64 bit) and BI haven't never do anything to fix it, so I'd be very surprised if one day they do something for that.
I hope I'll be surprised...