It's very complex, and difficult to explain in one post. You really are better served by reading documentation or watching videos.
I can try and tell you what I do know though.
It operates on top of TCP/IP, and uses standardized AES encryption I believe, but uses multiple layers of it. Files that are uploaded are broken up into 1mb chunks, which are encrypted and duplicated 4 times through the network nodes, so if someone drops, the chunk is still available, and it always makes sure there's 4 at any given time. The "vaults" that store the data (user run), take on different jobs for the network, either being routing nodes, or file service nodes. There's no way to anticipate what your vault will be at any given time, nor is there a way to control what it will be because that is decided automatically by the network, which helps to thwart Sybil attacks. This system means that there's no way to know exactly who is grabbing what data and from where. Even if you could see the IP of the person requesting the file, you'd only have a 1mb encrypted chunk.
Authentication is done via self-authentication. You have an account secret and a pass phrase. The account secret locates the files on the network, and the passphrase decrypts it.
As for the currency, it uses... Well I can't remember what its called atm, but basically the closest nodes (not physically, it's based on IP addresses and XOR routing, I don't fully understand it yet) determine whether or not they agree that the transaction is valid. I think it's 30 nodes, and something like 24 have to agree.
As for the master coin thing idk what you're referring to, but the maidsafe coins that are available are really just tokens that will exchange 1:1 with Safecoin on the safe network when Safecoin is ready and deployed.