Game Mechanics: Sebilis Crypt - area near crypt door has pathing issues

[DoucLangur]

The undead roamer did not spawn (or had fallen below zone?) in the past couple of days.

Also, I dragged 2 corpses exactly to the doorline of the crypt, and when someone came to pick up his corpse, it was gone - when I went to check myself, I saw that the 2nd corpse (troll form) had sunk into the floor half way. So it seems the one corpse fell below the zone and the other was about to do the same.

Appreciated if someone can look into this, I never experienced this behaviour before.