I don't use it, so I'm not sure if it works 100% but here: http://wiibrew.org/wiki/Gamecube_Saver
I've tried NuGaSa, Gamecube Saver and GCMM before and GCMM for me has the best results for extrcting GameCube saves.
Did you try the memory card on each slot? or you can just buy a MadCatz memory card or some other 3rd party memory card.
Why not just you link the source?:Newer version: http://dl.dropbox.co...cmm_r12_Wii.rar