I dedicated two evenings, totaling about 6-7 hours in all to reading the practice cases in the back of First Aid Step II CS. It has been a year and a half since i've done a family medicine outpatient-y type of rotation. The first two cases of the CS were a little bumpy, as I was still a little nervous about the exam. After that, you really do get into a grove as you push through the rest of the patients. The day goes by much quicker than you think.
I won't lie to you, I missed some questions to ask with patients, as well as missing some physical exam maneuvers. I didn't have any encounter where I thought I nailed everything, but I felt like I got most of the data down to generate a good differential and lab workup list. But I never forgot to wash hands, address patient by name, gown patient, summarize the patient's problem, counsel them about drinking or smoking if they gave me a history suggestive of excess, and discuss my differential and plan with the patient before leaving the room. One thing I feel that I might get dinged on is that I was pretty much rapid firing questions at the patient during the history taking, without showing too much empathy except for a patient I had where he could have been suffering from depression.
I don't have my results yet, so yeah... Don't sweat the test man, in hindsight, I sweat the test way too much and got worked up over nothing.