What are the titles of the demo songs on the Kawai cn270, and where
can I find the sheet music?

As there doesn't appear to be a way to enter an answer, I'm leaving a
comment so that future searchers might be helped.  I had the very same
inquiry and found out the following information.  This is a list of
demo songs used on most Kawai models:

Concert Grand 770/970 -	Etude, op.10-5 / Chopin
Concert Grand 750/950 - Brahms Rhapsody in G Minor
Concert Grand ES1/ESX - Brahms Rhapsody in G Minor
Concert Grand CN pianos - Brahms Rhapsody in G Minor
Studio Grand - Original
Mellow Grand - La Fille aux Cheveux de Lin / Debussy
Modern Piano - Original
Rock Piano - Original
Classic E.Piano - Original
Modern E.P. 1 -	Original
Modern E.P. 2 - Original
Drawbars Jazz Organ - Original
Drawbar Organ 1 - Original
Drawbar Organ 2 - Original
Church Organ - Toccata / Eugene Gigout
Church Organ CA750/950 - Unknown
Diapason - Wohl mir, daß ich Jesum habe / Bach
Full Ensemble -	Original
Harpsichord - French Suite No. 6 / Bach
Harpsichord (CA750/950) - Unknown 
Harpsichord Oct. - Prelude in Ab / Bach
Clavi -	Original
Mallets Vibraphone - Original
Strings/String Ens - Four Seasons / Vivaldi
Strings (CA750/950) - Original
Slow Strings - Original
String Pad - Original
Choir/Pad Choir - Original
Atmosphere - Original
New Age Pad - Original
Wood Bass - Original
Elec Bass - Original
W. Bass/wRide - Original

I was particularly interested in finding out what piece is the demo
song for the concert grand setting, and it is indeed Brahm's Rhapsody
in G Minor.  As for finding the sheet music, a quick Google search
should be fruitful or check sheetmusicdirect.us.