Re: Boom rise with reefing... How much?
Your topping lift should support the boom during the reef... simply luff the sail, drop it, tighten the reef tack, then the clew, then rehoist the halyard and tension. Remember to leave enough ease on the vang to absorb your boom lift (which must have been built into the sail by the sailmaker) - btw the angle of the reef 'foot' should be readily visible when the sail is fully deployed. If the reefed 'foot' line doesn't look as angled as the boom ends up it would seem that something's not set/tightened quite right during the reefing process. Having said that, though, I'd think that boom drop would be a more likely problem when people fail to adequately re-hoist the sail after putting a reef in.
Pictures would help tremendously here!....
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)