You made sure that everyone is using the exact same game? I.e. your dumps should be 100% the same. Make sure your and your friends haven't done anything like try to trimming the game to reduce its size or anything, or have attempted to do any mods. Last but not least, make sure it's the same region (e.g. you shouldn't mix NTSC-U and PAL versions). It might be a good idea to have everyone grab the MD5 hash of their copies of Brawl and make sure each one matches (Dolphin can generate the MD5 hash, right-click the game in Dolphin's menu -> Properties -> Info -> Compute).
It shouldn't. But to avoid any problems (as far as troubleshooting goes), everyone should be using the exact same setup anyway.
Quote:I have a question. What if he has opengl and i have something different? Does that cause any problems?
It shouldn't. But to avoid any problems (as far as troubleshooting goes), everyone should be using the exact same setup anyway.