AFE is CAA lasors recommended. No offence to J Pratt but I wouldn't recommend it based on my results on the PPL confuser.
I don't recall having any problem with the confuser after reading the Pratt books. I suggest the problem may be a bit closer to home, think you'd be best to re read them as it sounds like they may not have sunk in quite as well as you think.
They give you more info than you need but
if you have understood it you shouldn't have a problem with the PPL simplifier, confuser or the exam.