For those who want to enable 'Create Monster' from the GM interface, follow these simple steps:
1. Using your favourite hex editor, open up gs.
2. Go to offset 0x000C92AE
3. The byte sequence there should be 75 05, if not, then you may have another version of gs which I am not able to help you with unless you send a link to it.
4. Change 75 05 to EB 05
[NEW] 4.5 repeat step 2 to 4 with offset 0x000C9046, this is for the 'Create Creature' GM option, which lets you choose from some stuff that does stuff.
5. Save
6. Upload to your game server in gamed/
7. Profit
Note: This is only for the gs file included in the package from this thread.
Cheers
EDIT:
Don't forget to restart all your maps after doing this.
EDIT2:
Added Create Creature fix
qwename
Ragezone