You can add any emulator you want as homebrews in the apps folder.
GC2Wiimote is still a WIP and some games don't work. Same goes for general Wii games compatibility.
Those emulators require the MX chip iirc, not sure if Gman relocated that
BBLoader can be booted without installing it. Just press B when it asks you to install it (will ask everytime though).
Yeah compatibility is not perfect yet. I may look into it, but GC2Wiimote will only be updated in BBLoader from now on
If it doesn't show up it's either because you copied it in the wrong folder or because you still have the SD card inserted in the front of your Wii and the homebrew channel is just listing the homebrews on your SD card