Definitely circle answers on your test booklet. It may slow you down a few fractions of a second, but if you do mess up your bubbling, you can quickly go back and find where you got lost and correct the error.
I usually do 3-4 minutes depending on how difficult the passage is and spend anywhere from 45 seconds to a minute answering the questions. In total, you should dedicate about 8:45 seconds per passage.
then yes, def need to work on your fundamentals and if your rushing BR at all make sure you slow down. maybe even write down why each answer is right or wrong
That not be a question I'd be comfortable answering or hearing the answer to.. After all the race is long and hard and in the end, it's only with yourself. But that's just me.