John,
Well done for finding the forum, a great start to Cherubing (who cares if it's a word? I like it!)
Things to bring:
warm sailing kit (warm enough to capsize lots and wait in the water if things go wrong)
a buoyancy aid (safety first)
a trapeze harness (if you don't have one I'm sure you can borrow one)
gloves (some people use "racing cheese-wire" for sheets)
a towel (if you get cold you can warm up in the shower)
sleeping apparatus (i'm not sure what bedding is included with the bunk-house)
When you get to Rutland you'll see lots of Cherubs on the grass in front of the clubhouse where I've arranged for us to rig. If you make yourself known to anyone we'll get you matched to a boat.
If there's anything else I can do to help let me know. If you need to get hold of me, my number os 07751 233 667.
Cheers
Stu