So, I am currently building a giant catapulting range at the entrance of my fortress to destroy my enemies, but my dwarves keep walking through it when I forbid the main entrance doors to protect them. There has to be a path for the invaders but my dwarves switch to using my death chamber to get out, so I thought it would be nice to be able to just forbid my dwarves from ever going in there. Borrowing them doesn't work either because I need a few dwarves to be free to pull the levers.