I don't know whether the Sega Grand Pianist uses MIDI or some
proprietary software unique to it, but what I have heard is that only
the pre-installed music plays with the specific correct key action.
Other input is possible with random keys responding for the look.

Since the product release is still only in Japan, little info seems
to be available as yet.  I don't know if it is selling well over there;
I don't think that any of the ones on eBay have sold.  Besides the
instructions being in Japanese, the LCD window showing tune selections
or status (under the sliding music rack) reads in Japanese.  Has anyone
seen this cutie in the plastic flesh as yet?

Jim Katz =^..^=