There is no "rename" built-in, however you may read the existing key/values, write the new key/values and then delete the original key.

Look in the KiXtart manual for:
  • EnumKey(), EnumValue to enumerate the keys and values,
  • ReadtType() to get the value type.
  • ReadValue() to get the value value.
  • WriteValue() to write the value / create the key.
  • DelKey(), DelValue() to delete the old value(s) and key


Note, this may lose any associated permissions.

You might also like to look at SaveKey() and LoadKey() to shortcut some of the work.