Hello dclepoudre,
Thank you for pointing this out this error, we are working on a permanent resolution for this situation.
As a workaround, you can navigate to your personal tax profile under the 'Profile' tab, then edit 'Instalment Payments'. Set the amount to zero, then click continue. Although you've cleared this field, the original imported amount will remain on your return. You can confirm this prior to Netfiling by checking box 476 of your T1-General on your .pdf copy.
Hope this helps.
