1) Voting isn't compulsory. The townies have no one to bail them out this time - if they don't try to win, they won't win. So I see no reason to force them to put in an effort.
2) Coin flip.
3) The mafia isn't as impotent as you might think. True, they can't kill as frequently, but they have other advantages to make up for it. For one thing, there's alot of them: normally, in a game this size, there'd be three mafia members, here, there's five. For another, because the townies lack alot of the knowledge they'd normally have (the townies don't have an investigator, and don't learn the identities of the people they vote out right away), the mafia should have an easier time manipulating the townies' votes.
Believe it or not, I was actually worried I was making it too easy for the mafia to pull off kills. In the
original rules, which I was trying to recreate, there is no limit on how often the players can continue. Also, even when players rest, the mafia is in no way guaranteed a kill. Each "mafia night", everyone writes something down on a piece of paper: townies write "honest", and mafia members write down the name of the person they wish to kill. A kill is only carried out if each mafia member has written down the same name...which is hard because there is no way of communicating privately.