configuration storage not always right

Configuration storage should follow those rules:
     when the game is just unziped/untared somewhere, use rc.config in the directory.
     when the game is installed via package or other system specific method, it should use guidelines of this particular system:
           use xdg infos on linux, if existing, .config/usf otherwise.
           use AppData/usf in user directory on windows 7 (can be slightly different in other windows versions).
           don't know about where on OSX. any information welcomed.