PathfindingService + Narrow hallways?

Hello, I'm not sure how many of you have used the new PathfindingService(http://wiki.roblox.com/index.php?title=Pathfinding) but I'm encountering problems with it in my game. Basically, my game features procedurally generated maps, but due to the way I've made them, sometimes it will create a box that caves in on itself. To counter this, I planned to use the new PathfindingService to see if everywhere in the maze could be accessed. The problem occurs in the fact that my hallways are 4 studs wide, and the pathfinding seems to depend on making paths that have start and finish points at least 4 studs from any walls. To try and count this, I was looking on the service's wiki page, and I had found this property(http://wiki.roblox.com/index.php?title=API:Class/PathfindingService/EmptyCutoff), although setting it lower than the default of 0.16 seems to do nothing to help, and setting it above 0.3 seems to break pathfinding altogether.

I'm really stuck on how to go about this, any help will be appreciated.