I was trying WiiMC by streaming videos over an SMB share.
I noticed that on some specific videos, if you press the home button to bring up the file browser, and then hover the cursor over the system settings button, everything completely freezes and requires me to force the Wii to restart. But if you are quick enough, you can press the system settings button before it freezes.
I’m pretty sure this must have something to do with the little bubble that pops up when you hover over it, saying “system” (or something like that).
I have only tested WiiMC with SMB streaming and commercial DVDs, and I only experienced this on some SMB streamed videos, not DVDs or the majority of videos in my SMB share. Maybe it’s the specs of the videos that makes the difference, although I can’t see any difference (all DivX .AVIs). If you want any more details I’ll try to find out for you.