umm..I tyink its pretty much follow the path were guys are shooting at you...Thier are certian force fields that in order to get past you need to use the grav gun sucking power (alt fire) in order to pull those little ball thingys out of thier tube or whatever areas..sorta like pulling out a plug out of the socket but its the ball things.
Btw I did get stuck near that part once when i backtracked and a force field came up that wouldnty let me pass..I had to relaod and do again and the force field wasnt their that time..so if you REALLY get stuck its possible that could have happened...
Another part on that levle is an elevator you have to go up...sorry if this didnt help i ant tell EXACTLY where you are in this level..here if you want a in-depth faq
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