Clique extradata field, used to define PoA validators/sealers must match the following format:
First part: 32bytes vanity, meaning whatever you want here since it's expressed as an hex string (64 chars long as one byte is 2 chars), here in the example it's just zeros.
Second part: concatenated list of sealers/validators nodes addresses. Each address written ...
Web3 and Metamask are all you need to connect to Rinkeby. You don't need Infura, Geth, or Parity. For state modifying, check out the method send command:
myContract.methods.myMethod([param1[, param2[, ...]]]).send(options[, callback])
Well it is a testnet.
Without knowing what has happened here are some alternatives:
1) Some new network feature is being tested and it didn't work out very well (unlikely option)
2) There simply aren't enough validators online
3) The tools I (we?) use to check the status are malfunctioning
4) Some other malfunction in the network. Unlikely.
We have a Kotti Faucet here: http://kottifaucet.me/
You'll need to use your social media account to request funds by tweeting out and sharing the link to your tweet in the form. Instructions are found in the link I shared
You can follow my guide for running Kotti so you can test out ETC's POA testnet: https://medium.com/ethereum-classic/kotti-solidity-etc-...