The software download for the practice exams does not install properly, and will give errors that the file is corrupted. In order to install, download the latest version of 'Adobe Air' as of today's date 9/9/21 is no longer supported/maintained by Adobe themselves, but by a subsidiary of Samsung 'HARMAN'. You can download the newest version of Air from their website. After it's been installed, go back to the downloaded files from the Oracle installer package and click the JavaExams.air file to complete installation.
There are a few solutions available to correct this issue with a google search, but this one I found to be the easiest.