I first play the game, so it will make a game save. Then i load this app, and "backup" the file to my sd card. Then i open my sd card on my computer and view the file. I then copy the full name of the file, deleted it, and paste the name on my downloaded game save. Then i load the app, and "restore" the file to my gamecube memory card. Works great.
I used an official gamecube memory card. I know this way works because the same save file i tried copying didnt copy until i made it a certain name. I'm sorry i'm not good at making step-by-steps off the top of my head, i'll make a guide soon. --Crwys