When trying to edit any field of a report with a previously customized layout, all changes (header bands or column sizes for example) made in the option "Design report" are lost and the layout/report must be re-customized.
If the Change Auditor Client is closed and re-opened, however, the report design is then displayed as expected. The emailed report is also correct.
Close and re-open the Change Auditor Client to reflect the report design properly if frequent updates are being made to report design/layout.
Waiting fix in a future release of Change Auditor