1.) One of the powerful Captains in your Family disapproves of your elevation to the top spot. What do you do about it?

In this cases the best things is the lupara bianca,the best things is to kidnap the capo and make the body disappear perhaps by dissolving it in acid or in a crematorium,this will be an excellent warning to other capos to don't question your leadership,and of course made the new capo,the best earner of the crew;

2.) Two of the other Families are conspiring to get rid of One of the other Bosses (you are neither a fan or enemy necessarily of the guy. What do you do about it?

I would ask the bosses of the two families what they can offer me in exchange for my support.

3.) You end up going to the Can for a minimum of 10yrs. What do you do?

I would appoint my trusted man as acting boss and give him enough freedom of action except for the induction,people to kill ecc.

As boss I would set up a fund to make sure that even the brokesters can afford a good lawyer, pay bail, etc. (like in the old times),for the drugs I will ban from directly dealing with drugs but not from financing the purchase of drugs to sell it to others and share the profits (like Scarfo sr with the meth).
I would hire electronic surveillance experts to periodically check that there are no FBI bugs.

For the other things,don't be greed,let someone earnes,made only the best best earners or the stand up guys and don't whack someone if not necessary.