I recently finished my ATPLs and still have access to the BGS bank, for Performance it is out of 35 marks, Flight Planning is out of 43 marks, Gnav is 60 marks and POF is 44 marks. Bare in mind that is marks not questions, as each question on the bank counts for one mark I think. If I remember rightly there were a few questions in my Flight Planning and Gnav exams that counted for 2 marks, so this would mean you may have less questions to do than the amount of marks I have posted.