Can't review student's work

I have 3 students who have completed their VOKIs and are still at the 'Get Started' status after saving. I cannot preview them for some reason. I have successfully set up another student (Ty'relle), previewed his VOKI and his is now sitting in the 'Try Again' status. I am wondering if it has something to do with the fact that, after saving, the students found that they could not use the 'close' button but had to use the 'x' in the toop right hand corner of the 'close' box? Otherwise they did everything else the same way in which I set up Ty'relle's.