@Pixie
Actually I saw that in some SGOTM games. I used to set reminders before, but sometimes AI doesn't have enough money, so this is better. Makes you aware all the time. Yeah, other notes are also begs.
Regarding UN victory, people have to be friendly with you to give you a vote for victory, and that usually means +10 relations on deity, +9 on Immortal, I believe. Some AIs have lower tresholds, and monty usually takes +11. Also, if AI is friendly with both candidates, vote goes to one who he is friendlier with. Vassals always vote for their master if he is a candidate, and vote normally if he is not. You get relations by sharing religion, by BOTH of you having his favorite civic, by fair trade relations (gifting techs or money), by we appreciate years you have supplied us with resources, by mutual military struggle, by defensive pacts (be warned that defensive pact can have negative hit on relations with other civs if they don't like your buddie), by city liberation (+1.5 per city), and there is also you shared your technologies with us if you traded a lot of techs with someone. All these modifier's max value is determined by leaders. And all bonuses increase with time. And candidates always vote for themselves (except humans with free will).
Regarding becoming candidate for election, you must either build UN or be the largest or second largest civ (if largest one built UN) in terms of population, and that doesn't take population from demographics into account but is actually a sum of citizens which equals votes fot the UN (for example, if you had two cities, one size 11 and other size 7, you have 18 population and also 18 votes). If you're the largest civ sometimes it is smart to research mass media yourself and then trade it to someone who doesn't like you to build UN for you. There's no worse thing for UN victory than having your huge civ friend being candidate.
@Cossack date
I find that date a bit late, but it can work out on many maps. You can take out Lincoln, WK and montezuma on this map, but you can't do anything to Charlie and Joao.