Yes that was the day of all days! In the morning we were going for the world production record. Sailing a 105 litre Mistrl Energy within a few feet of the concrete in 60 knots of wind remains one of the stupidest things I've done on a windsurfer. We both did over 40 in the afternoon but it was too windy - we just couldn't sheet in, not helped by the sails of the day that had limited twist and over-powered very quickly.
We did sail the marine on port a couple of times but it was never as fast as the SW wind has to come over the hills. NW seems to be the best direction.
It sounds as if you're doing pretty well but the best general tips I can give are just let the gig pull you along - a lot of beefy speedsters dig in and try to muslcle it, drag it in and sail too much off the back foot. The broader it is the more you have to let yourself sail between your feet and even favour the front foot.
Sorry I can't help with Karpathos - I retired from the speed tour just before the event started there.
All the best and thanks for reading the forum