My note of entire process of launching a relay chain, connecting parachains, transferring assets between chains, and developing parachain runtimes.
Clone Wroking and compartibility.
polkadot build-spec --chain rococo-local --disable-default-bootnode > rococo-custom-plain.json
-- Alice KeyID
--chain rococo-custom.json
--tmp
--ws-port 9955
--port 30334
--bob
--bootnodes /ip4/127.0.0.1/tcp/30333/p2p/PeerID