I was not able to use the Arpegiator when my Kawai K5000R Rack was
running OS 4.04. I loaded OS 4.03 back into my Kawai K5000R Rack and
now the arpegiator works.

I will post the 4.03 OS for the K5000R Rack and K5000S Keyboard in the
files section in case anyone else has this problem. I also posted text
and Word document files called "How to Upgrade K5000 OS" which
describes the file handling and button pushes necessary to reboot the
OS in both the K5000R and K5000S.