I would section it off. For starters to test it, I would use some semi-transparent overlays that are invisible in runtime to test out how to do it. I did this a long while back in Multimedia Fusion 2, but that was a long time ago.
A good practice, however, would be to keep your rooms on an even grid. You want a camera object that NEVER goes outside the DEFINED area your character is in, that way you can get to the side of the "grid space" without the camera going over to another "grid space".
I'm at work right now, myself, but I'm sure I could get an example of this at some point later on.