The initial wording in the conversation had me 100% believing the book would be found on the first level.
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Perhaps we could reword it to the book 'may' be found on [insert level] but could be anywhere in the caves.
Real adventurer wouldn't need those hints though anyway

I liked the Searching mechanism. I literally scoured the entire upper level checking each room as i thought the search checks needed to be in a specific small radius of the items point. Turn's out that "search a different area" literally means search a different Map.
Started getting the proper tracking pings when I was on the right map.
I happened to be in the caves with two other characters at the time, purely by random chance (they were not on the quest). There may have been a chance that one of those other characters could have picked up the book... and I may have never found it? Fortunately I found it first.
Is this a feasible risk, or is there some item pickup protection in place?
I really enjoyed the quest and concept. It went smoothly once I understood how I was meant to perform it all. It didn't take long and wasn't overly complicated.