I got practice codes and Nintendont loads up fine and boots the game up but when I try to change levels it doesnt work,also save/loads Mario position doesnt work either. Can anyone help? I'm using the SD and USB technique.

Try loading your game through Configurable usb loader r70, with the default gc loader set to nintendont in settings, then enable cheats on your game and load it. then while in nintendont, enable cheats on your game also and launch.

If this doesn't work, idk. I use this method for paper mario ttyd

Make sure you enable cheats in the Nintendont menu. This should be on by default, but apparently it's not always the case.

Thanks guys, that was the problem, cheats were set to off. :)