Okay, using this online javascript TweetNacl encryption toolkit:https://tweetnacl.js.org/#/sign
sign your bitcoin address just provided and copy/paste the public key you used to sign it, and you're in as a backup tester, meaning you'll get $5 BTC to join and more if you are needed as a backup at any point over the next three days, which chances are you will be needed since its unlikely everyone will remember to check this thread every day for three days!

I've got to go for now and will check back in about 13 hours to relay you the funds and such.