Issues with completing the OTS EPP Courses in LEO can be corrected by doing the following:
In Internet Explorer:
Go to Tools>Compatibility View Settings and make sure la.gov is not in the list AND uncheck the "Display intranet sites in Compatibility View".
Open Chrome and type this into the address bar:
Chrome://flags/#allow-sync-xhr-in-page-dismissal (tip: make sure to include Chrome:)
You should see the below now and will need to change the dropdown of the highlighted one to "Enabled:.
Close Chrome and then relaunch Chrome and start the training.