Alternate routes?

[BR5555]

It was said that in L4D2 certain paths will be blocked sometimes, and other times you play they won't be, ultimately forcing you to not take the same path every time you play. Some people have mentioned this being in the demo but I've only encountered it twice, and in the same area.

In first level in the... bar, I guess... with the juke box, sometimes the door behind the register is boarded up, but, at least for me, it usually isn't.

I have never encountered any other instances, yet people are saying they have. I've searched every path I know of every time I play - they are all always open except for that one on occasion (twice).

So what are some of these other paths that may get blocked off?

[rpalace]

I know the first strip of shops in TP1 alternates. I think I counted 3 different paths in that strip alone. It's a bit hard to describe since it looks the same.

[xRedd13]

Yea in the area with the jukebox the route alternates every time. I haven't seen it anywhere else though. I'm sure the full game will be full of alternate routes though.

[Sykopathic]

AFter the Jukebox outside there are two areas that go through one with stairs and a fence that sometimes has a large chainlink fence blocking it and another archway before it that is sometimes sealed off with bricks.

[BR5555]

I finally got the chain link fence for the first time. I still have never seen the bricked up archway though. I guess I'm just unlucky enough (or lucky enough?) to be offered multiple routes most of the time.