its not that they are asking you to memorize screens, the questions will have a purpose to illustrate that you understand the function that is being discussed. as an example, if you don't know the different load balancing choices for dvSwitches, then you probably don't know much about virtual switching, or at least enough to understand the different choices and options.
Overall I thought the test was very fair, and a very good test of deciding if you really do know the basics of vSphere beyond just simple administration. It's VMware Certified Proffesional, not VMware Certified Administrator. There is a big difference between the two.
Perhaps they should offer an Administrator cert like Red Hat/Cisco do.