This is what I have found out so far: The quest begins with Avery he tells you about treasure Ricardo kept in a warehouse near Britain Wharf. Where he means is on the map marked 'clue' in there is a chest double click it to get a lantern. You wear the lantern, light it up and go to the position in that map marked 'Ruins' there is a book you can read. Once you have read it you go to Lt Dan (marked in the first map) speak to him then claim your reward from his chest. I have marked runes to these spots in a runebook on my shop floor, West of Zento. Feel free to use them. Thanks to Heimlich for taking me through Avery, And apologies Avery for eating your dinner.