If you experience a persistent 'Waiting for the system check to finish' message when attempting a Proctortrack onboarding or graded exam, please delete the text in the URL that occurs after this pattern, i.e " session/sdf2309u059uwednksjii78y/". The value after ''/session/' is alway unique. The one mentioned here is just an example. Next, add #/auto-connect to the URL of the page, and click to refresh the browser.
If you are still stuck, please reach out to edX Support at info@edX.org.