I think we need to document techniques for regulating older harps, as many harpists and some technicians do not seem to have the training or experience to know what to do, particularly in the wire strings.
One problem one can have is a buzz between the string and the stationary post. Putting a small piece of felt between them can eliminate that problem, but one must be careful when putting anything on the string that it will not dull the sound. The groove in the nut can be filed to change the alignment to fix problems with the intervals. Some stationary nuts can be replace with the new adjustable type.