Is f1 paper asked in too depth?

Yes. Even if you complete all materials and a Kaplan (acca authorized publisher), there is no guarantee you will be able to answer everything. The key thing is to understand the concept of everything, as well as, memorize them because the exam paper will have questions that require both : Your own understanding of the topic and how accurately you remember it. In my opinion, BT is the toughest foundation level exam. Glad I cleared it and can move on now.