I'm having an issue in Mission 2 of Thief 2 (Shipping and Receiving) where a number of guards who I'm assuming were supposed to be patrolling on the metal walkways on the 2nd floor of Building A are now on the ground floor in a couple of places close to said metal walkways, some in awkward places where I am now forced to use the walkways above them to get by. I've applied T2Fix to the game as well as the HD Mod where graphics are concerned and for the life of me cannot figure out what's causing the problem.

Any help or advice would be greatly appreciated.