Vales' guide sections 9 & 10 contains the following information on inserting new accounts into your local loginserver table.
insert into tblLoginServerAccounts (AccountName, AccountPassword, AccountEmail, LastLoginDate, LastIPAddress) values('Admin', sha('password'), 'admin@somewhere.com', now(), '127.0.0.1');
I've not tried multiple logins yet as I've not been successful connecting to world over LAN, but I have tried various different accounts with success. I normally restarted mysql (from cmd prompt NET STOP MYSQL then NET START MYSQL) to refresh the database once the new DB and tables have been added and updated.