@ Tom - Here are the answers, keeping in mind each one is based on the premise in your first paragraph:
a) If the game cannot be resumed before 10 p.m., which is the curfew for the Major Division, the game is over. The umpire is required to wait a half-hour (see Rule 3.10-b), or, in this case, 28 minutes, before calling the game.
b) Game is over.
c) The curfew imposed by Little League is the only "official" curfew. So an artificial or locally imposed curfew is treated differently. Because of that, the game was not suspended by rule, and if either manager protests properly, the game must be resumed at a later date. However, the local league could request from the Charter Committee that its locally-imposed curfew carry the same weight at the Little League rules. See page 12 of the rule books for that process.
d) This would be the same answer as (c) above. It does not matter that the locally-imposed curfew is by a municipality or the local league itself. Again, the local league could request from the Charter Committee that its locally-imposed curfew carry the same weight at the Little League rules.
e) The umpire does not have the authority to call the game in this situation. If either manager protests it properly, the game must be resumed.
The curfew (10 p.m. in the case of the Majors Division) applies to each day, not just weekdays.