I understand you need to be in column to enter a City or Town hex, however can I have my tanks who is already in a town or city after entering it in column be out of column and station there to fire out on enemy units or "must" I always be in column even though I'm not moving anymore?
The WED Exclusive Rules say "A Wheeled or Tracked Unit in a City may not leave Column." (2.9) Same for a Town (2.8).
Probably worth mentioning that in TGD it is allowed. So I guess someone could make the argument for house ruling that. As written though, the answer is no, tanks (aka Tracked) cannot get out of Column in a City or Town hex. Same for Wheeled Units.