Long story - so I got it all sorted which took about an hour of very intense endeavour and brought up the sail (modified, David C, as you suggested - how good is that!). Got it all connected to its bits of string and its pole, set up the boat to run downwind on the other poled out sail to cut down the apparent wind and - gulp - hoisted it. Foolishly, I hoisted from the mast because when, inevitably, it got away from me and unrolled itself, I had no control over it cos no turn on a winch. Boat doing 5 knots, sail pretending to be a thrashing prawn net in the water, Muggins cursing and pulling it in bit by bit and re-bagging it, but no longer neatly rolled so no chance of an immediate second go.
At this point, after clearing away pole and attendant clobber, engaged in Long Consultation with Wendy's Friend from the Liffey and reconsidered. First, the sail must be woolled just like a kite but second - why ever did I try to put it up with the pole and all the clobber already rigged? Upped the complication by a power of 10. Should have just thrown it up and got it properly tensioned and then set up the clobber and unfurled it.
A rest and another go and I'll get it right. Immensely useful but frustrating - you really learn when you have to do it yourself and get it right first time.
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