I intalled recently a wiikey on my wii and it worked fine with the 1.9b firmware and the wii console have the 3.0 one. I burned an meroid image and when i put it it told me that an upgrade was necesary for the game to play and I upgraded it and now only the original games work and when i insert a backup it appears as always but after I press start to start the game it says that there is a problem with the disk, please refer to the manual, and it happens with all my backups now. Someone else have been through the same problem??
When i had to update my wii with 3.0 my backups wouldnt work anymore at all, maybe it was an older modchip i don't know but they replaced it and everything works now, i had to go to the extent of taking it back.