How did you know my name? Oh well, I'd prefer to be called by Travis, I'm just wondering how you got it? Links from my website?
Starting going up the first flight of stairs with Cass...
OK, let's see. Just push her a little up the stairs. A lot on Agent, but not a lot on PA or she might fall through for some gay reason. At the top, be sure to open the door for her then go quickly into the corner and when she gets up there, push her through. Run up a little so that cass will not get too far away from you and shoot the guard before he can do something gay like throw an N-bomb. Then push her a little, not too much, until you turn the corner on the ramp, and when she is about halfway up, run ahead of her and open the first door, and rush into the corner facing out. When she starts to go through the door then push her. The guard may or may not be in the way. If he is, just fire at him. Even if it's risky, because it's too costly when cass gets through and you're stuck on the gay guard for a second and she starts bitchin. Then push her a little again, and run ahead of her really quickly to get on the other side of the stairs. That way she won't run around them, but she will go up them (takes some luck/frustration out of it). Then push her a little, but be sure to ALWAYs stay behind her during this. Don't get her out of your sight or you'll probably be in her way. When you get to the last turn, just left strafe really fast up there. You might go past her, but sometimes you push her and it saves good time.
I haven't played this level in at least a month or 2, but I hope I could still be of help. That's the stuff after cass's room.