Kate,
I'm fascinated you managed to buy a new sail without knowing the sheeting position!
The track is to provide the appropriate ( albeit small) amount of adjustment likely to be necesaary to be able to open the leech when you need to.
My No.3/blade is not intended to reef, just furl, and has vertical leech battens, but no sacrificial strip.
It should be possible to arrange a block shackled to a pad-eye. I had a similar arrangement on my GK 29, 15 odd years ago. There, the pad-eye was installed just at the turn of the deck/coachroof where the glass was nice and thick. I simply spread the load with "penny" washers.
Whilst I think the same approach would do in the "lobby" in the 275, I have doubts about the WC compartment because of the compressibility of the "lining" I referred to in my previous post on this thread. You may well need to spread the load significantly wider OR ream out the "liner" back to the solid glass of the deckhead.
Apropos of nothing, I think you posted previously that you had a carbon-fibre Spinny pole on "Beeline"? If so can you tell me who supplied it and how you get on with it?
275/30 "Cascada"