Exam simulator - 6000 unique questions, would HIGHLY recommend
It's not free, but well worth it in my opinion.
The key to this exam really is intensive, repetitive training for the brain to be able to tackle these tricky exam problems.
I've noticed that people who have failed in the past, including myself, always wish they would have done much, much more practice problems.
Hope this helps a lot of you frustrated with your exam results. I've been there too and know how frustrating it is. Good luck!