So I took someone's advice, and started WAY back at the entrance of Spellhold in order to NOT kill the captain and be able to leave other than direct to Elf City. Problem is, he gave me a quest (as I'm sure you know) to get a horn. I can't figure a way to get it and not wake the couple, and once that happens...even with the horn...there's no one around on board either ship to ge tme outta Dodge...wat am I screwing up???

I dont think you can help being spotted by the couple, just kill the guards and head towards the right side of the docks where you find the captain.