Please don't use MultiModManager (MMM), it's closed sources and not updated for vWii.
Use Yet Another Wad Manager Mod english version instead. (YAWMM)
it's updated for vWii, has a lot of safety checks to prevent bricks. (but still, don't try to install IOS or system menu on vWii, you will brick)
like said, it's included in the softmod guides, or direct link here:
http://www.hacksden.com/showthread.php/7241-YAWMM-DE-English-Translation