I'm not sure if this is even related to ustealth, but who knows...
My USB HDD isn't detected by anything on vWii unless I unplug it on the vWii menu and then reconnect it. Once reconnected, my loaders detect it as normal. This is the same whether it's ustealthed or not.
Long story short, I have to disconnect and reconnect the drive each time I start vWii. If I don't, vWii won't detect it at all. Is this a known problem with certain drives, and are there any workarounds?
EDIT: I've confirmed that this has nothing to do with ustealth. My USB HDD just has the drive initialization issue (apparently this is common with newer drive controllers) and only initializes properly with IOS58. So for anyone searching this thread for the same issue, what worked for me is using USB Loader GX, going into "Loader Settings" and setting "Loader's IOS" to "IOS 58". Also, it does NOT work from the forwarder channel, only when launched from the Homebrew Channel. And finally I had to disconnect my Wii U USB before powering on. This was the only way I could get it to detect the Wii drive without reconnecting it at the vWii menu.
Im having this exact same problem with a WD passport 4TB drive. MBR FAT32.
Before installing ustealth I never noticed as I was connecting the drive post vWii boot....Now I can leave it connected but doing so renders it useless.
Really hope theres a workaround for this.