Yep - tried the arrow keys trick already (it really worked previously when I was in similar situation - actually the same just with happy ending) - This happend already x times to me but after few desperate tries of mouse clicks or using the arrow keyb keys I somehow boarded my ship again - this time nothing works (and I was trying it like for x hours - as this is my very good hero on impossible that was just getting exp prior he will kick Korador) - and I overwirtten all previous saves - because I decided to fight my UPDGRADE battels (artefact battles) on this small island... before each I pressed F5 - 6 battles - autosave is like 5 hours old
so now are not working the arrow keys not the ultimate on-boat clicking mayhems... still stuck on the island