The Lost Book ~ Scroll of Retrace

Quest: The Lost Book
Start NPC: Yoran Oran @ (J-9)Door: Rhinostery in Windurst Water [S]
Items needed: Mythril Beastcoin, Vellum, Linx Pelt
Reward: Scroll of Retrace

Walkthrough:
Click the Rhinostery door @ (J-9) in the southern part of Windurst Waters (S) for a cut-scene. This cut-scene begins the quest "The Lost Book".
Travel to Giddeus in the present, bring a Mythril Beastcoin.
On the first map drop down @ (G-8), travel north and go the Storage Room @ (G-6) on the lower map.
Once inside the Storage Room, speak to Quu Bokye, a Yagudo NPC. He asks for a Mythril Beastcoin.
Trade Quu Bokye the Mythril Beastcoin and he'll give you a Leather-bound Book (key item).
Return to Windurst Waters (S) and touch the Rhinostery door@(J-9) again to return the Leather-bound Book in another cut-scene with Yoran-Oran.
Now travel to the North part of Windurst Waters (S) and click on the door of the Optistery @ (F-8) for a cut-scene with Yoran-Oran and Tosuka-Porika. You will be asked for a Lynx Pelt and a sheet of Vellum.
You must travel to Castle Oztroja (S) to G-8 and click on the ??? to obtain the (key item) Lynx Pelt.
Just wait until the Yagudo in the room turn around.
Return to Windurst Waters [S] and trade a sheet of Vellum to Door:Optistery for another cutscene. Vellum can be made with Leathercrafting or purchased at AH.
Wait until next game day (no need to zone), then return to the Optistery for the final cutscene and your reard of scroll of Retrace.