So the problem with the JPN Berry Glitch Shiny Zigzagoon is that it doesn't load on real hardware once extracted from the "Interactive Multi-Game Demo Disc - January 2004 (Japan)" disc.
To the best of my knowledge there is no way to load from the disc's menu system (unless i'm missing the obvious, having explored the menu the best I can without been able to read Japanese).
However the menu system on the disc is able to launch a Mario Kart Double Dash Demo, which is done via the kart_try_go.html, located in local > kart folder
You will also see a folder called pokemonrs in the "local" folder, in this folder the pokemonrs_p.html contains the parameters required to launch the Berry Glitch Shiny Zigzagoon distribution.
This is: <meta name="go-tgc" content="/local/tgc/Ruby_And_Sapphire_Rev param=file://client.bin">
So we can simply edit the kart_try_go.html in the kart folder to launch the Berry Glitch Shiny Zigzagoon distribution like so:
You will notice i've also removed most of the comments from the HTML code, this is to ensure the filesize is not larger than the file it's replacing, as GC-Tool will only allow you to replace a file that is the same size or smaller, not larger.
You can then right click and replace your modified file with GC-Tool:
After that you can load the ISO on real hardware and activate the distribution like so:
Be aware you don't put the GBA in multiboot mode, load the distribution on the GameCube and press "A" to get to the second screen, then power on the GBA and let it load Pokemon Ruby or Sapphire load and it should try distribute all been well.
However you will notice I seem to get an error when trying to distribute the Zigzagoon.
I think this is because the battery in my JPN Pokemon Ruby is dead, so it would be pointless in trying to fix the glitch and fails?
With that in mind does anyone have a JPN Pokemon Ruby / Sapphire cart with a working battery and the ability to test this to see if it works?