I didn't understand at first what you meant by those questions, so I wasn't sure how to respond, also because I haven't touched anything with map generation except the resource generation lua to be sure about my answers. But now that you have found the answers yourself I anderstand what you meant, and both answers are correct.
"GameEvents.PlotOwnershipChanged" and "GameEvents.PlotPropertyChanged" both are working, but like with many Civ VI (Game) Events, their triggering is not consistent, so sometimes they may not trigger, even if they should. "GameEvents.PlotPropertyChanged" I think isn't meant when chnaging the owner of a tile (property), but when a Map Tile has received a property, its property has changed or got assigned another one. take a look at the RedDeath Scenario files to see how it's used by the devs.
Many People describe Forums as an Old form for Discussions, and Discord is the new "Forum" for Discussions. I like how Forums are well organised and stractured, and you can easily search for Things, but Discord is pretty simple and much more handier and you can easily navigate through the Servers and Channels, though as you have guessed, it's not as organised as in a Forum and no way for Google to find a Post/Thread.
I suppose you mean the Unit cycling when selecting a Unit and then having assigned a task to that Unit so the game automaticly selects another Unit. Yeah, that's annoying in late game. I think there is a Mod that prevents that or it has an option to stop that, but I can't remember its name. Maybe CQUI or CUI Reloaded. The function for that is I think in UnitPanel.lua or UnitFlagManage.lua:
THXThanks to Suktritact here's a very usefull collection of events and objects: https://sukritact.github.io/Civilization-VI-Modding-Knowledge-Base/
Good luck!
-- Building
INSERT INTO "Types" ("Type", "Kind") VALUES
('BUILDING_EXAMPLE', 'KIND_BUILDING');
INSERT INTO "Buildings" ("BuildingType", "Name", "Description", "Cost", "MaxPlayerInstances") VALUES
('BUILDING_EXAMPLE', 'LOC_BUILDING_EXAMPLE_NAME', 'LOC_BUILDING_EXAMPLE_DESCRIPTION', 0, 0);
-- Requirement
INSERT INTO "Requirements" ("RequirementId", "RequirementType") VALUES
('REQUIRES_EXAMPLE_POPULATION_20', 'REQUIREMENT_CITY_HAS_X_POPULATION');
INSERT INTO "RequirementArguments" ("RequirementId", "Name", "Type", "Value") VALUES
('REQUIRES_EXAMPLE_POPULATION_20', 'Amount', 'ARGTYPE_IDENTITY', 20);
-- RequirementSet
INSERT INTO "RequirementSets" ("RequirementSetId", "RequirementSetType") VALUES
('REQ_SET_REQUIRES_EXAMPLE_POPULATION_20', 'REQUIREMENTSET_TEST_ALL');
INSERT INTO "RequirementSetRequirements" ("RequirementSetId", "RequirementId") VALUES
('REQ_SET_REQUIRES_EXAMPLE_POPULATION_20', 'REQUIRES_EXAMPLE_POPULATION_20');
-- Modifier
INSERT INTO "Modifiers" ("ModifierId", "ModifierType", "RunOnce", "Permanent") VALUES
('MOD_BUILDING_EXAMPLE', 'MODIFIER_SINGLE_CITY_GRANT_BUILDING_IN_CITY_IGNORE', 1, 1);
INSERT INTO "ModifierArguments" ("ModifierId", "Name", "Type", "Value") VALUES
('MOD_BUILDING_EXAMPLE', 'BuildingType', 'ARGTYPE_IDENTITY', 'BUILDING_EXAMPLE');
-- Modifier (attach)
INSERT INTO "Modifiers" ("ModifierId", "ModifierType", "SubjectRequirementSetId") VALUES
('TRAIT_ATTACH_MOD_BUILDING_EXAMPLE', 'MODIFIER_ALL_CITIES_ATTACH_MODIFIER', 'REQ_SET_REQUIRES_EXAMPLE_POPULATION_20');
INSERT INTO "ModifierArguments" ("ModifierId", "Name", "Type", "Value") VALUES
('TRAIT_ATTACH_MOD_BUILDING_EXAMPLE', 'ModifierId', 'ARGTYPE_IDENTITY', 'MOD_BUILDING_EXAMPLE');
-- TraitModifiers (attach)
INSERT INTO "TraitModifiers" ("TraitType", "ModifierId") VALUES
('TRAIT_LEADER_MAJOR_CIV', 'TRAIT_ATTACH_MOD_BUILDING_EXAMPLE');INSERT INTO Buildings (BuildingType, Name, Description, Cost, InternalOnly)
VALUES ('BUILDING_EXAMPLE', 'LOC_BUILDING_EXAMPLE_NAME', 'LOC_BUILDING_EXAMPLE_DESCRIPTION', 0, 0);
