Create a new entry in the XML file for your game using Wordpad or Editor. It could look like this (this is no Japanese ROM but Sappy failed):
Of course, we don't know the offset yet cause Sappy won't find the Songtable.
But there is a tool for that I found a long time ago on the internet. I have no clue who is the maker of it (so no credits here) but I can give you a download link:
You can scan any ROM you want for it but it will usually always output an offset; even if the game does not use the MP2K engine (that's how the music engine of Nintendo is called like). Always pick the offset of the first line. I don't know what the offset of the other lines are used for.
So finally you got the offset and you can paste it in to your XML entry and run Sappy and everything should work. Of course you should type in the correct Gamecode and other information and not just copy my XML entry.
So if you are crazy and don't want to do it by the mainstream way, this is the way to go ;-)
Wow I never heard that about that before
I will insert the link when I will have power