Who are you studying with? I am currently with Open Study College and from the Level 2 Package I found that you need to get a grasp of everything to do with manual bookkeeping that is in the course (So not the computerised package bits) in order to geth through both exams.
I passed my B1 a couple of weeks ago and have done the B2 mock and will be doing the exam over the next couple of days.
The B1 was more calculation based and what entries go into what ledgers and the B2 is about VAT, CIS, Day books and companies, legislations etc.
I would suggest you pay for and complete the mocks, I found this hugely beneficial. The whole Mock and Exam process is very straightforward.
Hope this helps