The registration at the game server is as simple as possible: you just have to enter your alias/name and a password. If the name is already in use, it is matched against the password. Otherwise the name will be added to the database along with the password and the date of registration, and you are known by this alias in future. For convenience, the password is stored locally as plain text. So take care to use no security relevant information.
The use of the game server is free of any charge and you will not get bothered with ads. Also your email address will not used for other purpose than information about new messages or if it's your turn (take a look at asynchronous games for these features). Subject to decision are violations of the common netiquette.
The server itself runs on a Raspberry 2 SoC (previously it was a SheevaPlug), online 24/7. Since the broadband connection is disconnected daily it might happen that the connection is lost for some minutes until the IP address is renewed (this happens usually around 2am UTC). The communication with the game server is done via TCP/IP on port 5001. Please take care to have this port not blocked.