which gx loader version are you using ? Grab the latest revision from the site (919.dol) rename the file after you download to boot.dol and replace the boot.dol file on your sd card in the apps/usbloader_gx folder. Downloads - usbloader-gui
Don't worry about the ios236 missing it's a printf statement they had to do some debugging. Remove the config directory before using the new version (conflicting configs otherwise) and launch it from the homebrew channel to ensure your using the sd. I'd suggest either cios rev 14, 17 or 19. These are generally avaiable and most people are running one of those versions. I'm currently on rev 19 myself working fine.