Registry Fast auto generate a backup confirmation dialog before any repairs are made. You could disable this setting by clicking 'Do not automatically backup...' in 'options' tab.

To restore registry do the following:

1. Click the BACKUP tab, and click 'full backup' button.
   
2. Select the backup(s) you wish to restore. Click "Restore" button to begin the restore process.
   
3. A confirmtioan dialog will be displayed asking you to confirm your choice to restore the selected repairs.
4. Click Yes to continue.