It's a Wonderful World: War or Peace

No. The campaign has six scenarios, but you play only five, in order unless a scenario says otherwise (p. 15).

Yes: unless a campaign card explicitly changes them, the player with the most Victory Points wins. Scenario rules and Campaign card effects take priority over the normal rules (p. 15).

Yes. Keep orange Campaign cards until the end of the campaign, but return any Resources or Characters on them to the Supplies at the end of each scenario. Grey cards are discarded at the end of the scenario (p. 15).

Keep your Partisan card secret during play and reveal it at the end. Each faction totals its members’ Victory Points and divides by the number of players in that faction; the faction with the higher average wins (p. 5).

Yes. Espionage is optional when you reveal your drafted card; each time you swap it with a card in the Common area, advance the marker one space. Once it reaches the final space it stops moving, but players can still perform Espionage (p. 7).