They are using an old version of themida, get some olly plugins and simply run the game in olly.
Wait for GG splash to popup and pause the process, take a look at callstack and nop the init clal of gameguard.
Manipulate the JE to JMP so no error pops up and then fix the 5 switch-cases which check gameguard state when you enter the loading screen.
It will run for 3 minutes, then the server will kick you for wrong heartbeat