It roughly behaves like a mission. You can enter and exit it as long as you have the quests. No binding / recall is possible.
At the moment, it seems that if ALL the team leaves the zone (or dies), the zone resets and all the mobs respawn. So maybe one person staying safe near the entrance is a good option.
I talked to Means (FC's monsters dev.) today on test (yes he works on Sundays). Means thinks that two persons can beat Albtraum but that it would be extremely long. This is what he asked me to test.
Well... I can tell you... two persons can do it, if they have quite good heals, but better go with a team of orgmates unless you want to spend a full night in Albtraum. Also the final boss could be tough.
More details below.... but some minor spoilers.....
To get to Albtraum, you need to go to the valley of The dead, where the quest Yuttos are in their tents.
There are steps that lead to an upper plateau with another tent. In that tent stands The One Who Sees Dead People, a Yuttos.
Talk to him. If you are teamed, he will give you a series of missions, each one with a reward.
Enter Albtraum by a portal nearby.
The zone is full of level 260 mobs of various kinds. Almost each mob drops items that will have some use, sometimes.
North of the zone is the Altar of Summoning where you can summon Albtraum "pocket bosses", and get a final boss.
Going to the altar from the entrance at level 220 is like going from Ravine statue in Penumbra to the first unredeemed city in Penumbra at level 200: the density of mobs is about the same but most of them are also the mobs you need to kill for your missions, so it's not that bad.
Oh, I forgot, when you kill a mob and think you're good "something bad" may happen...
And what else?... Some pictures, but we'll discover Albtraum together in AP teams!
The portal in the valley of the dead
First steps in Albtraum
The map (you have the minimap, even if you don't have Inferno map running)
Something bad may happen as I said... guess what....
The altar
Also see Ancient Spirit Stims, under Pharmacy, and the Ice of Albtraum Arrows.