Also to clarify, the point of doing this is not just being able to playback these files, but more importantly to edit them, replace them by other- higher quality sounds.
So what I really need to do is open these big files (each of them contains many different sounds, which I found because they are already playable and somehow audible in audio editing software Audiocity). Then find and select any sound in that long file, replace the selected sound, save the file and re-import all that back in the game..