Full explanation is, the GC Freeloader on there doesn't work full stop. Just tested it out, and it hangs on the Freeloader screen. I Google'd it and this has been around for at least a week, and no-one's got it to work.
Apparently it's to do with the fact the GC Freeloader is being run in Wii mode when booted via the homebrew channel, and so it won't run a GameCube game.
Basically, when the Wii changes from Wii mode to GC mode it cannot detect the SD card or the Wii's memory (just like a GC can't), meaning it's pretty much impossible to run a GC Freeloader without a modchip. It might still be possible, but I wouldn't exactly wait for it to happen.
Actually, just thought a bit after I said that lol, would it be possible to somehow move the bootable onto the GC memory card (basically use it as an *SD Card* that can be read in GC mode) and run it from there? Or is that not possible?