Well, I passed through the Eternal Maze, and I'm in the library.

But, I keep dying from Damian's henchmen in the library.

What do I do?

I'm level 11.

O, Level 11 is low!!!
The best thing to do is to reach a "waypoint shrine", there is one just past the library
inside that Maxos Temple! Run through the library, maybe use a skill so the Black Rings can't see you, use shrine and go first to explore Brocken Valley or go visit the Orobas Fjords (youmeet there Level 18 enemies, but when I was level 13, I kill a few of them ... !

I'm sure you didn't all area and/or quest, because Level 11 is low! Good luck!

I go in the Maxos Temple when I was at least level 15 or 16.

Oh right. I'll do that.

Okay, where do I go to do the 'Into Thin Air' Quest?

I'm at the Citadel Tower, but don't know where to go.

Citadel Tower? You mean the "Lovis Tower", in Brocken Valley?

I don't remember that quest ... strange ... maybe I miss that quest...
What's "the description" of that quest (see logbook) ?Who or what gives you this quest ?

'Into Thin Air' quest right ??? Do you remember there is a locked door near the teleport by the lake under Lovis Tower ??? Now go in there , and be prepare.

@ggm261: Okay! Thanks!

@Joram: Jeoff gives the quest after you give Father Romon the Scyring Stone. You go into the Chapel, and Jeoff tells you that he's gone missing, and Romon left some notes on the alter in the Chapel

Even when you used the stone yourself first.