I wrote that code and only really recommend using it with Reader (since there's no other option) or with Acrobat if the original blank non-corrupted form is not available. The script only makes the field value visible, it doesn't and can't restore any missing keystroke/format/validation/calculation scripts (which includes all of the built-in methods) that can have a significant impact on what should be displayed in the fields. So if you have access to Acrobat and the original form, it's best to export the form data from the corrupted form and import it into a blank form.
For forms that include scripting or show/hide field actions that control the visibility of the fields, even this may not result in the data being properly displayed, so it's a good idea to create a special version of the form just for this purpose where all of the fields are set to be visible.