Thanks for getting back to me.
I guess what I want to do cannot be done. I was looking for a simple way to designate a combination of keys for controlling the volume. I got used to being able to use the three keys that were designated for such on the Apple keyboard i.e. to the right hand side of the layout.
I have the "slider" in the Menu Bar . . . but I like the way that the "key" method allowed the volume to increase/decrease in increments or, with one touch, Mute the sound altogether.
I was hoping there would be a way to re-designate three keys to perform the same functions on the new keyboard (up/down/mute).
But, alas, it was not meant to be . . .
Thanks for your help anyway.