[AccessD] Max of 20 values

Arthur,

I sent you a class solution offline.

The assumption was that you wanted to lock all but the currently available control and then walk 
through the controls allowing just the next control to become enabled.

I did a little coloring since it is free.

It would be possible to unlock the previous for editing if necessary.  That adds additional logic 
and I didn't want to obscure what I am doing with that code until the specs call for it.  ;)

John W. Colby
www.ColbyConsulting.com