Try installing it via the homebrew browser.
If that doesn't work, try either GeeXbox or the much better WiiMC (Which can also be found on the HomeBrew Browser). In fact, I recommend WiiMC more than the MPlayer and GeeXbox (http://wiimc.googlecode.com/files/WiiMC%20Channel%20Installer%201.6.zip).
http://wiibrew.org/wiki/Homebrew_Browser
If that doesn't work, try either GeeXbox or the much better WiiMC (Which can also be found on the HomeBrew Browser). In fact, I recommend WiiMC more than the MPlayer and GeeXbox (http://wiimc.googlecode.com/files/WiiMC%20Channel%20Installer%201.6.zip).
http://wiibrew.org/wiki/Homebrew_Browser
To the new WiiMC's (and all the Tantrics apps) you need the Oficial IOS 58. You can download the Tantric's IOS58 installer or do it your self downloading from NUS Downloader and installing with wad manager.
