Disklavier

I am a very new member of this group--we have only owned our DKV 
MarkIV for a couple of weeks.  Thanks to Carol Beigel's website (well 
worth a visit, by the way), I have now found an excellent source of 
MIDI files of classical music.  For example, I found a file there of 
Beethoven's Emperor's concerto.  However, when I played one of those 
files on our DKV, we only received music through the speakers, not 
from the keyboard.  Thus, we need to find a way to redirect the piano 
track data in that MIDI file to our DKV's keyboard in order to get 
the real benefit of the music.   From Carol's notes we may also want 
to adjust the volume settings on some of the MIDI files that we 
download. 

To do that we will need to use some sort of MIDI utility.  There 
appear to be plenty of them available for PCs.  I have not yet found 
such a utility that runs on Macs, even after spending some time today 
in the Apple forums.   Does anyone have a recommendation for a simple 
MIDI utility (i.e., capable of adjusting volume and redirecting track 
data to our DKV keyboard) that runs on a Mac?

Any recommendations much appreciated.

Mike M.