Also, I don't know if that is the same app, but I was using a gui autoboot iso, but it was not working. You can open the iso in hex and see if the title id is patched to 0 for the first letter. Or just try bootme, or wit.
The one that wasn't working was Wii Autoboot Creator. It doesn't do anything and I hate telling people how to use Bootme so I made the app Krafter linked above. I can assure you it does what it's supposed to.
Cogita ante salis
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