You are now a 3rd year and powerpoints is a thing of the past, just like Step 1 you will need good high yield review books and rotation specific study guides. As far as I understand all 3rd years now have to do the MUA courses (online) which would help tremendously for CS and rotations itself. There are many resources on the MUA courses platform that can be accessed, journals etc. In hospital using UpTwoDate can be great while on rotation. The hospital I rotate at gives students free access.
Having completed all core exams I can shed some light on CCE. These exams are not easy, by any means. I know in the past people were simply studying Exammaster (EM) questions and getting fantastic grades. I think MUA and SABA have changed exams and no longer use old EM exams. That being said, I would still do all the EM questions for each rotation as the CCE Q are from EM Qbanks and the questions are really stupid sometimes, poorly written and test minutiae not even UW tests on. I would also do all UW questions for the rotation. This would have a two-prong effect, it will help you pass the CCE and you would have a major investment towards CK. I am firmly of the opinion that UW done over and over again through 3rd year would give you a great CK score. Any book of your choosing (step UP etc) can be used as an addendum.