I played it over my friends house. Its hard because not only do you have to have you squad trust you you have to keep they're fear down or they will kill themselves. If they dont trust you they will kill you. And this is putting aside the big enemies you will have to kill.
They have a trust level lol. When its 100% they help you fight off guys that dont trust you. In green, which is still good, they will do what you say. Orange they wont do what you say but wont attack you either. Red the suspect you of being the thing and will try to kill you at some point.
Giving them weapons and ammo increases tryst and lowers fear some. Also killing baddies in front of them helps.
My input is, the movie is f00king gory and sick, but u want game input, well read some damn reviews from ign and gamespot, they give ya the whole breakdown silly pants