ohh, you are right, I didn't thought about it being an extracted pack from emuNAND into a wad. I didn't know there were that much DLC.
sorry I spoke like I knew it all
Like I said above, the file is not provided with a nfo, readme or anything to explain how to use/install it?
Xflak thought the same thing than me, but I'll add details.
So, I think this wad has been created by installing all DLCs on emuNAND/Neek, and then using a tool to pack all the files in the DLC folder (small files, not 4GB+) into a big wad file. For example BlueDumpMod, or ShowMiiNAND.
The wad is big because it has a lot of small files in it, and once you install it back to emuNAND you don't care about being in FAT32 because you'll have small files back into the DLC folder.
the big wad file can be located on a NTFS partition, then use a wad manager to install/unpack it to your emuNAND.
I'm more curious to know why ShowMiiWads didn't recognize your wad file. Maybe it has a size check? like I said games are supposed to be 40MB max, and therefore could have a check on file size to prevent installing anything bigger.
I'm also curious to see the file content, if you could send me just the header (like for example 1MB? no copyright in it, it's the header) it should contain the file list, checksum and the location where the files are meant to be installed to.
There are other tools to extract wads, like Wadder, or CustomizeMii, you could extract the wad on your computer, and copy the files manually on emuNAND, or repack it in parts.
or even on Wii with some wad managers capable of installing to emuNAND, or usbloadergx.
what you can try :
put the wad on NTFS partition
put your emuNAND on FAT32 partition (sd or usb)
use an emuNAND you don't care (or make a backup first), or make a new NAND dump, on FAT32 partition with enough free space (4 or 5GB)
from USBLoaderGX: try to install that wad from the wad installer tool in the features menu.
I'm curious to see if USBGX detects it as bad wad too, or if it sees its file content just fine. it might crash because of memory issue, but shouldn't put 4GB in memory at once so there's a chance it can work.
note that it might take a lot of time to parse 4GB, let it do the work until its completed or you have an error message. if you force shutdown the process it can corrupt your partition.