1. So you're trying to suggest that the Bible is an instruction manual for using a car we don't understand? I'd say the analogy is more like there's a car, and then different groups of people are offering their best idea of the manual. The car didn't come with a manual.
2. Did you choose your parents? No. So therefore every decision you make is not fully within your control. C.S. Lewis uses this analogy to clarify what loving your neighbor as yourself means. Basically - you should understand that if you were in another's shoes you'd be doing exactly what they were doing. Your 'free will' was handed to you.
3. No, we have logic and reason which can help us create theories to test claims. There are only claims - and not all claims are equally as logical. Extraordinary claims such as the immaculate conception and defying death require extraordinary evidence. We could have video evidence of Moses parting the Red Sea but that wouldn't mean Jesus is the Son of God.