First of all, thank you for your detailed tutorial.

I am new to crypto currencies and i want to create my own coin but not for the market, but for payment processing in small festival.

I successfully cloned and created 4 nodes of litecoin-core, and changed everything to match with my coin, but i am stuck for some things now.

I have several questions:

I used https://github.com/tiagosh/AltcoinGenerator to bootstrap everything

1. I am using -regtest parameter and i can successfully add blocks in each node and earn coins. First of all, how nodes know to communicate? Is there main node which is updating every other node in network? How current nodes know about new nodes?

2. Are that 4 nodes actually miners? How can I setup them to automatically mine and processing transactions, because i don't want payment platform to be decentralized, but only built on top of litecoin so it can scale to decentralized model if needed. Festival is small event and there are about 5000 people there which should be able to have wallets and make transactions, so i suppose it would need big number of miners?

3. How can i build mobile wallet? First of all, do you need actual node for every wallet? How can I create wallets which only can pay without actual nodes? And how to create mobile wallet which can send and pay? Is this possible with JSON-RPC api which exists in litecoin-core?

Applications should be SO SIMPLE, only to have qr code of wallet to receive, and also possibility to scan other qr code wallet and to send there.

So my main understandings are:

How nodes know about each other, is there centralizes api node?
How wallets know about nodes, where mobile wallet is sending request for making payment?
Can I make simple HTML5 and JAVASCRIPT wallet applications? It doesn't need to have whole blockchain on it just to be able to make transactions.

For last one, my basic idea is to have one node ( but dont know how to communicate with it? RPC-API? What is endpoint? server-ip:port? )
which is used for all payments or maybe to have node per wallet, but it will be on server and simple app will just communicating with it via some protocol? Is this secure? Are there flaws for this system? I tried to find litecoin-core for mobile but there is not.

So, somebody will ask me why just you dont build centralized database payment system instead?

Because I want to learn about blockchain step by step
Because it already have great code base for secure ledger balance processing which i need and i want to try working with it.

Sorry if my post is confused, but i have so much questions and need to start somewhere.

Thanks