It is not necessary to register an address if you are a user of Moon Bitcoin, Moon Litecoin, Moon Dogecoin. Your address is already registered.Make sure yourself.
http://coinpot.co/ Click on "Find your wallet address" and enter your address.
By the way, on my Coinpot.co account I see all my earnings from Bonusbitcoin and Bitfun, but Moonbitcoin faucet are not connected to this account. To connect it, I need to sign a message or make a deposit from my btc address.