I have USB Loader GX and a few wbfs files on flash drive. I am using the top rear slot of the Wii U with no luck. When I load USB Loader GX it just fades to the 12 or so Wii boxed and returns to the Vwii dash. I have never used this program before so I am not sure what to expect. I get the same fade to the boxes and return to the Vwii dash with Wiiflow as well. Tried putting backups on the SD card in different folder structures as described here to no avail either.