This is because Priiloader on vWii is replacing a systemfile that usbloader gx is reading the assets from and therefore cannot show them correctly. It has nothing to do with "corrupeted files".
Are you playing as Katie or Nate? The new update I'm working on will polish up a lot of the mod and also fix a lot of the currently existing Quest bugs.
Make sure that your version of Atmosphere can handle the 17.0.0 firmware. If it is too old it will need to be updated also or you may not be able to boot the emunand after the firmware update.
I disabled the timer using idle3-tools in linux.
https://idle3-tools.sourceforge.net/
But you could check this link for some tools that may work via Windows. You may have to do it via the commandline though...
Have you turned off or changed the sleep mode on that WD disk? I know that there is a common problem for many of them to go to sleep too fast. I have had several that I had to disable sleep on to function properly on the Wii. By default they...
Rev 2 according to the serial (RVL-SMNP-EUR-B0) and md5.
You should check and verify your file using md5 or other checksum against the values from the redump page for the game (http://redump.org/disc/20088/)
And of course you have verified if this happens when you play your actual disk?
I have the game in question dumped from my original disk and it plays just fine in both usbloader gx and directly from disk.