I responded to your support ticket with some workarounds for this issue. For others who might encounter similar situations like this, here are some workarounds that might be suitable for their situation.
1. On the last question, change the feedback to “Immediate feedback”. The user will get immediate feedback when they choose an answer, then they can complete the test by clicking the Done button. Or, you can add a submit button to delay the response until the user clicks the “submit” button, gets feedback, then clicks on “Done” button to grade the test.
2. Change Question 10 to be the second to last page in the test. Have the normal Next button like the other 9 questions on this page to take the user to the next page. On this last page, tell them they have completed and then click the Done button to submit their answers.
Either of these workarounds will keep the feedback from interfering with the Processing of the Test.