Brewology

HI i have just installed the homebrew channel on my Wii and i cant add a savegame extractor or apps please can you help me. And when i try and load bootMii the screen goes blank please help thank you

You say you can't run any apps? is your SD card setup like this. (jus sum example apps)
root /
apps/
scogger
towerdefense

all apps must be called boot.dol, otherwise the homebrew channel doesn't pick them up.