Using the "Reset Activity" button on the PT Activity screen (by the "Check Results" button), results in the activity having a Guest username. This happens even if Guest has been disabled in the Activity Wizard>Answer Network>Settings>"No Guest Profile". Students have been earning zero points on a few of my labs as a result of this bug.

Further, the Guest is improperly trimmed. A space after the Guest username results in an allowed Guest username, which is then trimmed (somewhere) and when CTRL-SHIFT U is pressed the Guest user will not be allowed.