I am wondering why a student name would be missing while a vote is in progress.
I am using a student database. The student entered her PIN and registered the same as the rest of the class. When it came time to vote, the options appeared on the screen of the ActivExpression and she sent her answer, but her name did not appear on the screen with the other students, and her results were not recorded.
(I'm not sure if this is directly related, but I have had similar situations when students were the first name on their class's list in the database. I have had to add a dummy student at the beginning of the list.)