would be good enough to have it in the other thread and wait there for an answer.
gx is kind of old. use the mentioned loaders cfg usbloader or wiiflow and you shouldn't have problems.
you should stick to the fat32 guide as it also says **FAT32 USB Loading will only work with Hermes cIOS222/223 or with cIOSx Rev 19 or 20**
maybe you also need to update something as well.
also join the chat for minor questions if you like, always helpful people around.