Toward the end of the Guardian of Y'ffellon quest, after all the fighting on ship, Captain Siravaen says "come speak with me." I didn't see her, and I entered the Captain's Quarters directly below her instead (I followed the NPCs as they ran in). This sent me into a loop where I was transported to Y'ffellon, but the quest tool said to "Board the Mad Maiden".
I was able to take the rowboat on the shore of Y'ffelon back to Vastyr. That brought me to the docks at the beginning of the quest, with Sir Stefan speaking with Captain Siravaen. I was then able to take Siravaen's rowboat back to the Mad Maiden. I was spawned below decks but there was some sort of time out or border to where I was, because I was unable to get on deck to finish the quest. I tried running, and I tried waiting, but withing 20 seconds or so, I was spawned back to Y'ffelon and the quest tool said to Board the Mad Maiden again.
I did this loop about 4 times, when on the final time (as I was looking up if anyone else reported this), I arrived on ship and was instead prompted to defend the Maiden again. I fought through the ship battle again and this time was able to continue the quest as normal.
Seems the Captain's Quarters should be locked until prompted by the Captain to go below decks.
Huor Melwasul - Archdemon, The Demons of Light - Warlock, Hufflepuff House - ADXB1 - NA
I'm only updating this because we're commenting on a thread about signatures. Give me awesomes!