Hi all, just want to add some specific details here....
Recently, I put my SSBB into my USB in NTFS mode (a whole 6.93gb in one WBFS folder). In USB Loader GX, the file reads 0.0 gb, as if there's no file in there. Apparently, this is a current issue for USB Loader GX: Can't read DL DVD games (bigger than 4gb). This issue has been posted here:
Issue 1429 - usbloader-gui - NTFS duallayer doesn't work - Project Hosting on Google Code
The solution? Either you format your USB drive into FAT32 mode (which will split the file automatically into 2 chunks of file), or still using the NTFS mode, but go to Options --> Settings --> Fat32/NTFS --> WBFS Split Style --> 4gb (in Wii Backup Manager). That should do it, and cheers