When you achieve crafting level 5 you will receive a mail from the Office of the Harbormaster." Open it and accept the quest, and a Message in a Bottle and Blessing of the Prime''' recipe scroll will appear in inventory.
Scribe the recipe.
Take the bottle to your home and place it. Then right-click it and select "Read Message."
Search the wreckage. NOTE it's very hard to spot anything on this step in third person. Press F9 until you are in first person point of view to make it easier.
There's a book at 25, 0, 33
Gather ingredients on the island.
Get foodstuffs from a long-abandoned garden in the plowed field.
Get fuel from an old barrel of coal in the house.
Use the Makeshift Workbench in the house at 24, 1, 8 to make Blessing of the Prime.
Return to Raffik and use the Blessing of the Prime on him. (Target him, then activate the Blessing in inventory.)
Speak to Raffik.
To leave the island, use the boat at 80, 0, 28 . You will receive the next quest in the mail at level 10. DO NOT discard the bottle! You will need it later.