I also encountered this error today with version 1.1.2. However, only occurs when I plugged in a 2TB hard drive. When my 500GB HDD is plugged in, WiiMC still loads up fine and I can play movies from it. Both drives have the exact same setup–one WBFS partition, one NTFS partition–except the 2TB drive’s NTFS is 1200GB instead of 300GB.
I can also play movies from the 2TB when using MPlayer CE (6.80 r636), but WiiMC 1.1.2 can’t load at all while it’s plugged in. Also confirmed to work well with WiiMC 1.1.1, so must be a new bug with the latest update.