Very first session with this combo.
Wind: 7-12 with some gust 14 kt.
Water: nearly flat.
Fin: R17S
Crew: 3 other very good sailor (I was the 4th in the day ranking!)

In the beginning I've rigged up the sail with the recommended specs for DH and OH.
Mast base 1 cm back from middle.
Planning was easier than my '07 combo (161-warp 11,9) because the sail is much more "pumpable" than North.
Upwind angle was average,speed average too.But I had big problem to right close the gap without spinning out the fin.
In downwind reaching the nose was too low and,after a couple of scary back chop touches, finally happened what was expected! Boooommm!! Fast forward!! The board nose has gone broken and my faith has gone lost...
So back ashore and wanted go back home (very hurted!) but the guys convinced me to stay.Fixed the board and,after a few mins of mental relax,just downhauled 4 cm more (!) the sail,lenghted 2 cm the boom and gone back to the water.
Now the set up was much better.The board pointed a lot better and a very good balance was present.The angle remained similar but it was easier reach it.Downwind the board didn't stick or catch the small chop and I was the fastest in the water.
But I felt that something still lacked.So I've reared 2 cm more the mast base and reached 1 cm the boom height.Now the trim was REALLY balanced and the combo released some very good performance both up and down wind.I've easily fighted my battles and the results were less conditioned by the stuff.
A bit disppointed for having damaged the board but it's helped me a lot to think at the reason why it's happened and how to solve the problem.
Usually fw sails,when just rigged up on the floor,look ok.You watch at them and think you like it but once in the water (always with a sparring patner) things can be very different.
NEVER STOP TO TEST OUT!

bye