[SOLVED] Stuck at Black Magician's Lab

[PhD in Maths]

After following the passage in the tunnel between Zenumist and Alcando I arrived in this place; but it just looks like there's no way to get out of here. The way back had a lenghty fall and I couldn't climb it up. I hadn't even started the related quest so I have no idea what to do to proceed (or go back). Teleport home skills or Maple Guide teleports are not working either. Is there any way of getting out of here?

EDIT: this link has a video which shows the passage has a rope, but it doesn't exist for me http://forums.maplestory.nexon.net/discussion/14587/black-magicians-lab

EDIT2: Getting into Cash Shop at the hallway did the trick. I just started at the start of the passage