Hello I have a few questions...

-I already installed the homebrew channel via the letterbomb exploit. However I want to play a game back ups (these are mine before someone starts screaming pirate!)and I used usb loader gx with no luck. What are my doing wrong?
-When ever I go over to a friends and conenct to there wireless the Wii prompts me to updat eI have not done it because I do not know wether I can put the homebrew channel on it again...
-In order to play my own back ups I keep on reading about NANDS and stuff like that... help?

Thanks in advance :D