Fran,
Backwards compatible – the newer model can play the older model’s styles. The opposite is only possible if you rework the file with an outside program. Normally the results are fair. But – there were third party styles sold for the Kn2000.

This is opinion; Do not use the keyboard by trying to make it do what it was not intended to do. Use the keyboard as it was intended and enjoy what so many have found to be good. It's an old keyboard with a special sound, no more. Many keyboard users have held an older model refusing to part with it. Psr 2100, Psr3100, Dx7 they were like old friends offering a great special feeling that their newer keyboards did not. This is the value of the Kn2000.

I may have posted this before – My voice sounds much better on my Kn5000 then it does on the Kn7000 or Tyros3, go and figgure.

Hope this helps, John c.