That off the wall game in his comments :
"Yes, you are right. Manufacturing cost of 8M-bit HuCard was too high, and volume-type controller seemed to be mandatory for this game. So we gave up."
I don't see anything there that suggests the game is 8mbits. 2-4Mbits perhaps, Well at least the audio for all those games are pleasing. Thanks for the compilation of links.
I am liking with what I am seeing with Marble Madness and peter pack rat. The sound samples in that Peter Pack Rat port. The fact that they made this much progress and then not finish and have it released It's breaking my heart !__!
I am assuming the "volume-type controller" is something like these: