I did the following test using "Land_InvisibleBarrier_F" as object (see uploaded screenshot):

On the right I put down the barriers in their original size/scale leaving one side open, then I put an AI in the middle and gave it a waypoint on the other side and outside of the enclosed area. In the right example the AI detects the wall in front and to the sides, it will turn around and go either left or right to get out of the closed off area and then head back north to it's waypoint.

On the left I put down the same barriers, but scaled to "8" and placed 3 of them (due to the bigger size) like on the right side (all other settings are the same, I only put down a marker on the floor so I know exactly where the original size is). What happens there is that the AI goes straight North, only evading the barrier immediately to the north and only reacting to its original size!

The latter even happens if you explicitly "enableCollisionWith" the AI man! 

The weird thing though is that the same is not (!) true for the player: For a player the resized dimensions of the object are used in regards to collision detection (even without setting it explicitly).