Hi,
Yes, I have noticed that the screws have different lenghts when I opened the laptop: to be more precise 8 out of the 10 screws are long and 2 are short, but the short ones are at the very back of the laptop (where the heat sink is), so I didn't mixed screws and even if would have, the bump should have been on the back and not on the front and I even didn't forced the screws when I screw them back: I stopped when the screws have stopped to move (infact, when I tried to unscrew them, they immediately began to move). Also, do they not know the concept of screw limit?! If your device need long screws that, when screwing, do not have to screw indefinitely, by design you must use screw's limit. If they need an engineer to explain this concept to them, I'll apply for a job!
I can't even RMA'd it because I use it for my job everyday and I don't have any other powerful laptop! If this bump can degenerate and become a problem I should do it though.
I'm very disappointed!