The 8 core topics are the ones you need for the exam. You should be able to find this in the syllabus outline thing.
I did it last year... So long as you can write an essay and keep making things up you'll be fine.
Just keep writing for the entire 2 hours in the essays.
Although they rarely give band 6's so you just have to ensure your bs is better than everyone elses.
As for notes... I just found some online like 2 days before...