Really good.
What seemed like a very basic flash at first ended up being really cool. I was fooled by a lazy-looking first couple of seconds that the whole flash would be stale, but the music blending with the creepy smiles on the boxheads (as well as the awesome, nightmarish faces during the escape) just worked well. The only thing that seemed to get to me was adding the tiled picture of an office in the background. I feel you could've come up with something that would have worked just as well as everything else. Also, some cleaner lines would be nice. It looks like you got lazy with some of the scenes. (Note: I did read the author comments and realize that she probably was being lazy about it seeing as how this was the product of being lazy with other work.)
All in all, I really enjoyed this short piece, and if this is what your work looks like while in a state of insomnia and procrastinating, I can't wait to see the other important animations.