This post is actually about the Implementing Pega Customer Service 7.2.2 course, which is not available in the Courses drop-down on this form, but it may also apply to the 7.2 course.
The instructions for the last exercise in this course, Exercise: Updating an Interaction Goal, state to use the Architect OperatorID to log in to the exercise system. After failing to get in with that OperatorID, I logged in with the [email protected] OperatorID we were instructed to use for all previous exercises. The first thing I did was verify that the Architect OperatorID doesn't even exist (as you can see in the screenshot below). Then I went ahead and completed the exercise logged in as [email protected] with no issues.