Weird. I guess I would try making a gct of only one of those codes enabled and try that. that seems really odd though that none of them worked (because the codes definitely do work). I know this is trivial, but make sure you are using the codes for the right version. Did you try the infinite shield or either of the ones that toggle hitboxes?Hmmm... So I'm loading with GeckoOS using a real melee disc. The only one of your codes that seems to work is the up on the d-pad to start a match by yourself. All the other codes I've enabled (unlock everything, c-stick in 1p, default match settings) all work just fine as well. I am definitely player 1 on my Wii as well.
Any code I try to use to affect what the CPU does does not work. Player 2 CPU always just acts like a normal CPU.
I've tried Dios Mios and it sends me right back to the Wii menu when trying to load.