The lock has arrived in St. Maarten and with some luck will go back into the rig on Saturday to be tested under load.
In the end the major issue seems to movement of the lock body inside the mast due to an incorrect fastener, with the result that under load their was too much side force on the "bullet" for it to release.
A few photos of the lock in the test stand and the "wrong fastener" are attached. The masthead blueprint is included to give an idea of how the locks are installed in the mast.
I would love to do it. It was simply a scheduling matter, with KWRW, the Heineken, and St Bart's fitting more neatly into my work schedule this year. We will do the 600 or the Rolex Middle Sea race in the next 12-24 months.