Quote from: profedustream on Today at 10:52:36 AM

My first question is: is the master public key always used to update the wallet balance? Or is it only with ESP?

It's specifically specified in EPS' config to circumvent the full transaction index requirement,
and even if your server knows all of you future addresses, there wont be any issue since it's for personal use.

For other server implementations, servers only acquire the scriptHash (addresses) from the connected Electrum clients (rather, Electrum client asks the server).
Read the comment/code: github.com/spesmilo/electrum/blob/master/electrum/synchronizer.py#L131

Quote from: profedustream

However, my second question is: where does come this address, at which my 0,01 BTC had been sent? I mean: this address wasn't a hash from my master public key. How had it been created?

It's a 2-of-2 MultiSig address created from your and the other party's public key.

Quote from: profedustream

My third and last question is a bit stupid, but i wanna check: considering the last paragraph, does my Electrum wallet now use TOR to connect to nodes; hiddening my IP to them?

If the connection icon is 'blue' instead of 'green', it means that you're connected through Tor.