I passed too! Very very happy, got over 90% and still managed to miss a bunch of questions. Amazing.
I agree with everybody else, Dannemiller and painexam.com were very helpful.
I also attended the PassMachine course for Pain Medicine, which was very nice, but the lectures don't seem to line up so well with the test. If you can do the Dannemiller videos and attend the prep class like I did, I think that would prepare you very well. I also used a very small book by a shrink named Steven Stahl on pain meds and fibromyalgia which was extremely helpful.
EDIT: Also, I think they could have left every single image out of the exam and had the same results, what a waste of technology.