I managed to install Bootmii as boot2. However, it is not booting. And since I don't have a gamecube controller I cannot use the IOS version, to make a copy of my NAND. I've spend an evening searching GBAtemp and all the internet for a solution. Bottomline: it seems that my two SD-cards are not compatible. I've even tried to revert to Bootmii beta 1 because the SD card compatibility list on WiiBrew said one of my crads had better compatibility there. So, does anyone know, if there is an update of bootmii coming up soon that fixes the SD card compatibility issue?