If you add your own custom fields to the Transformation Designer project then it is necessary to regenerate the Invoice Processing validation form and then add your fields to the form. The Custom1 - Custom5 fields are already on the validation form. This means that you only need to regenerate the validation form if you have added additional custom fields.

If however, you are using the predefined custom fields, you may want to edit the name as it appears on the validation form. In that case, it is necessary to edit the custom field labels.

You can regenerate the validation form by following these steps: