Bricks, Masonry, Asphalt and Concrete - Attaching window boxes to brick exterior

Hello -

I live in a historic brick building that is undergoing some roof/brick repairs due to water damage, and window replacement for the entire building. The building is almost 100 years old, and has two layers of brick. The condominium owners would like to keep our window boxes, but the architect/project manager has not yet agreed to any of our solutions for attaching the window boxes. It is not an option to attach anything to the window frames (it will void our new window warranty). Here are my questions:

1) Do you know of any reason why screwing a small hook/screw into the utside layer of brick would comprimise the integrity of the building?
2) Do you know of any adhesive (epoxy? cement?) that we might use to attach a bracket to the surface of the brick, and then screw into the window boxes?
3) Do you know of any other solutions that I haven't considered? (I looked into a clamp, but we don't have enough of a lip/ridge to our exterior sill for that to work.)

Thank you.

What condition is the brick and mortar in? Do you have access to the inside of the wall or is it finished? Wall ties sound like what you need. Drill from the outside and tag a pressure treated 2x4 or 2x6 under your window and make your boxes out of Meritec or cedar and hide the treated piece. If the inside is unfinished, use all-thread rod and bolt the 2x4 all the way through the wall and cover the inside bolt with drywall and still hide the 2x4 on the outside with the box.

Hope this helps,
David