Hi Westcoaster, welcome to the infussion world, a great place to be!

Just place the cleat 1 cm back, but makesure it in line with the blocks under the beam.

the shock cord set up is simple, the set up guide is it, its that simple. (I know I dint belive it at first)you must appreciate that the shock cord will not take all of the slack of the tack line as the tack line moves approx 1.8m into the shute and the sock cord is approx 1m. The trick to ensure that the tack is comes loos every time is to make sure the tack line release ring is in front of the cleat, this is on the tensioned side of the sheet when the spinnker is up. Then the only thing the shock cord on the end of the tack line is doing is slightly tensioning the end of the tack line, ive just come back from the NACRA Championship in Holland and 90% of the infussions where set up like this, a few have modified the system with a tensioning block/shock cord under the tramp (shck cord running to the back of the port hull, through a block and tied of on the front tramp stb side) that runs between the rear block on the beam and the block on the stb hull side stay, this stops the skipper/crew from sitting on the tack line during retrival whilst leaving the end of the tack line at the same position, allowing tack line hoist whilst out on trapeze.

Well in regard to the spinnaker lines, you will need to have enough line to be able to trapeze of the back on the hull, and I mean the back, this is one of the tricks of sailing the infussion fast down wind, in force 4-5 winds, what the guys do and you maybe able to do the same is add a smaller sheet to the spinnaker sheet that goes into the shute, this will give you the extra length and make the spinnaker retrival easier, most of the top teams have this mod! this is a win win, latest mod and no money spent, just a littl time with a sewing needle

Hope you come right!