Life is Feudal: Your Own v0.5.5.2

You must run steam first before launching the game (for more safety use another steam account with no purchased games on it)

Run yo_cm_client_eng.exe or yo_cm_client_rus.exe

From the main menu press Alt + Z to join the server x20.
From the main menu press Alt + X to join the server x1.

OR

You can also connect to the server. Just open console by pressing 
CTRL + ~ 
and write

joinToRemoteServer("SERVER_IP_ADRESS:28000")

If you see CR_INVALID_VERSION message, you need update your game to the last version