I was able to use USB-loader on my Wii.
Recently i used WBFS-manager to transfer a game from a friends External HD to my own USB-drive.
After that, i couldn't even enter the USB-loader screen (via HBC, gives black screen). I didn't update my wii, or HBC, all i did was add this one game (Mario Kart) to my USB-drive.

I noticed the coloring (processing) on my USB-drive is very slow.

Anyone has an idea on this ?

Thanks in advance!