imputation of sin, original sin, existence of law - one of the great church debates

Romans 5:12-21 produced at least two topics for debate that were critical for ages and were vital in anyones faith. these are: (1) calvinism vs. arminianism and (2) imputation or non-imputation of Adam's sin to all men. i would like to focus on the latter, since the first already had its considerable share of a major thread here in BB.

Rather than discussing the concepts, i think i'll outline the major points of the debate and ask if you believe in them.

1. Adam's sin. Was it imputed to all men or not? By imputation it means that all of Adam's progeny were made personally guilty of the same sin, while not personally committing the same.

2. Sin Nature. Due to Adam's sin, men became sinful. thus, all men after him have are totally different in terms of ability to sin or not all his life. before the fall, Adam can be sinless all his life. after it, it is impossible for men not to sin due to the sin nature. what have you to say about this?

3. Was there a law from Adam to Moses? a debate caused by grammatical wars.

4. how much of a representative was Adam, or was he? when he sinned, does it mean that it is what we would certainly have done should we be on his place? or is he plainly the one to carry us all? or was it really just God's call to impute his sin to us?

5. are we condemned from birth? if so, are we responsible for it?

6. are we able to answer God's call, having the sin nature?

7. if Adam's sin caused our condemnation since birth, and if we are not able to answer God's calling, how are those not saved responsible for their own condemnation, seeing that the did not cause their own downfall, but were rather imputed to them apart from their voilition. indeed, even before they were able to decide?

This has been quite a topic for me, and i am into Calvin's book 2 as of now for reference, after a few commentaries.