I have 3 bots, necromancer, archer and a warsmith.
upon update i get this error code (error code 620 i think)when using OFFICIAL CLIENT to bot.
Ive done this for a couple of times already. and it works for me. follow these steps and if it works for you then give me some credit to it and say thanks.

Note: Use it at your own risk. if something happen to your account and your pointing your finger at me I WILL LAUGH AT YOU!.

1. look for the l2.bin in system folder copy into l2.exe
2. run l2tower and select l2.exe on system folder of the client.
3. since i have 3 bots i click 'run and inject 4x.
4. the first window that will load will get a error message(error code 620 i think) and the other windows will soon come out. notice that the GG is running already. dont close that 1st window with error message. wait for the others to load up. after the other 3 windows loads up, there will be no error message ont the other 3 and still GG is running.
5 close the 1st window and log on to the game.
6 enjoy now and its injected running along with GG without deleting it.

on my conclusion, GG only detects injections when startup only, but when already running it does not anymore.

Note: Use it at your own risk. if something happen to your account and your pointing your finger at me I WILL LAUGH AT YOU!.

System specs:
hp compaq 6510b(laptop)
win 7 ultimate
core 2 duo 1.8
128mb iGPU