The whole idea of this exact location of both landmarks thingy is that the area in the new level must be at list in the same size of the last area in the last level where the player was transported from. The landmark culculates the distence between it and the player then places the player in the same distence from the landmark in the other level, regardless if there is a brush in there.
So place the landmark at the same distence from the walls like the other.
Example: Landmark(level 1)- 8 units from the floor, 120 from the ceiling, 32 from the walls.
The other landmark mustn't be any closer to the brushes around it then the other is. The landmark's cordinates in hammer doesn't mean a thing.
Hope this explains the placement of landmarks a bit.
![:)](http://192.241.182.11/images/smilies/smile.png)
By the way: don't say you were stuck in the air, this way I thought you were just floating in the middle of your map. In the void/wall means you are outside your map.