If the network is full just join the next one down the list until you can join one.
Register an in game account
To register simply connect to hamachi and then follow this site http://holyran.sytes.net Click the register button and then you should be able to log-in the game.
Starting the game
To start the game click the launcher.exe in you ran client folder.
Note: If you cannot connect to the game this mean the either the HolyRan server is offline, you are not connected to hamachi, hamachi is having a problem, or that you do not have the latest patch/you have not patch your client properly.