I hear that a developer of Shakka-to is from Jaleco (and he had created some music game accused by Konami) and this series are too similar to Samba De Amigo by Sonic Team so that Yuji Naka gone to his development section to make a violent protest.
"Any company has no power to stop people emulating"
MAME is the emulator of no giving in the pressure from any company even if they don't allow