Thank you for sharing your situation and question with us.
According to the IRCC Call Centre, you may want to complete everything else and include handwritten totals in that section.
They suggested that you may also want to include a note stating that you were unable to complete it along with the rest of the information on the computer.
You may want to confirm this information by contacting the IRCC Call Centre directly.
I hope this information is helpful. Please let us know if you have further questions and if there is any follow up to your question/situation.