This is quite simple: the ROM file on the folder "content5" of the ISO is the game itself. It is LZH8 compressed. If you play the ROM after you uncompress it in an emulator, it works, but it has no sound. On the other hand, there's a PCM file on the same directory, which is also LZH8 compressed. I don't know if it is related in any way to the game sound, but it seems to be so... And there's a VAR file, too. Do you guys know what to do in order to merge this files, or to enable the sound on the ROM?