I recently played the "Vogelstruijs" side quest as well. As I recall, when I put to sea, the usual interface commands were unavailable, in particular "Sail To". When I'm doing a normal ship-hunting quest for a governor I can find the target by using "Sail To", it's usually the last ship on the list. Without that, I had to Direct Sail all the way around the island to find the Vogelstruijs. Fortunately the wind was fairly co-operative, but I suspect this quest will be a lot less fun if it's blowing from the east, straight into your face as you try to make your way from Port au Prince to Boca de Yuman.
Also, playing this side quest activated the "Smuggler's Life for Me" side quest. Can this please be removed? Partly because it was annoying to be stuck with a side quest I didn't want, and partly because it is highly illogical. Your job here is to kill a smuggler (and possibly his wife, depending on how that encounter goes), then destroy his ship - a smuggler's life is definitely not for you!