Gecko OS and GC Booter are the only apps that i know to boot GC Imports on an unmodded Wii.
But even with the latest GeckoOS, there are still Games like Shikigami No Shiro II (jap) or Wave Race Blue Storm (jap), displaying the "Error - Turn OFF Console" Message.
If you flash your Wii via RegionChanger to JAPANESE, you can boot them over the Diskchannel but you'll have graphic Errors (WaveRace) or your game is in strange 50Hz Mode (Shikigami). Also: If you boot via GeckoOS, the japanese Text is not messed up, if you boot over the Discchannel - Text is messed up.
But even with the latest GeckoOS, there are still Games like Shikigami No Shiro II (jap) or Wave Race Blue Storm (jap), displaying the "Error - Turn OFF Console" Message.
If you flash your Wii via RegionChanger to JAPANESE, you can boot them over the Diskchannel but you'll have graphic Errors (WaveRace) or your game is in strange 50Hz Mode (Shikigami). Also: If you boot via GeckoOS, the japanese Text is not messed up, if you boot over the Discchannel - Text is messed up.