@leejaclane
EmuNAND Save Mode
Off = Game saves will be read from and wrote to your NAND
Partial = Game saves will be read from and wrote to your EmuNAND save path
Full = Game saves and settings (e.g. Mii, Wiimote & network info) will be read from and wrote to your EmuNAND save path
So if you want your saves to go to your SD card or USB drive then the recommended option is partial. Although some games don't work when this setting is set to partial or full, which is why it's off by default.
This setting isn't supported via SD card mode because the d2x cIOS doesn't allow writes to your SD card while a games being read from it.
EmuNAND Channel Mode
Full = Read data from your EmuNAND channel path and save data to your EmuNAND channel path
Partial = Read data from your NAND and save data to your EmuNAND channel path
This setting should probably be removed, since nobody should ever need to use the partial option.