In those wierd corridor places, there's always purple energy walls which you can only see in alternate vision mode.
What are they for?
How do they work?

These purple energy walls seem to be the portals which teleport you around in the labyrinths if you walk through...

At first I thought that's what they were too, but I've found some of them that don't move you; instead they move themselves when you walk through.
The one on the far northwest does this.

They are teleports. If you go through one of them the map switches without you noticing it. You think you're in the same place but you've just been teleported to a different section looking just the same : congratulations, you're in a maze ! ^^

Mazes in Tölva can be really hard. The Dirac Undulation is driving me mad at the moment.

Ah yeah.
I just gave up on them.

In fact that one I referedd to in the northwest, I think is designed as an inescapable trap!