A list of the changed text files:
Required files - These files add fields required by Kingdoms
Data Folder:
battle_cfg.xml
Adds phalanx intercept_range.
Adds max_missle_range_extension.
descr_area_effects.xml
Adds boiling_oil effects.
descr_boiling_oil.txt
obvious.
descr_campaign_ai_db.xml
Adds some faction requirements.
descr_campaign_db.xml
Adds settings for unit sizes.
Adds setting for sally battles.
Changes assassination modifiers.
Adds new settings for spies.
Adds devastation and ambush settings.
descr_cursor_actions_battle_clasic.txt
Adds a bunch of settings regarding allies on the battle map.
descr_effects.txt
Adds path to boiling_oil.txt
descr_engines.txt
Adds great_cross_jerusalem.
Changes values for ladders.
Changes tortoise_ram and adds values
descr_engine_skeleton.txt
Changes ram engine.
descr_event_effects.txt
Adds boiling_oil
descr_event_images.txt
Changes chat_message settings.
Changes historic_event settings.
Adds footer_item
descr_mount.txt
Changes mass on several units.
Adds water trail effects to several units.
descr_projectile.txt
Adds dropped_projectile.
Changes accuracy on most units.
Adds some javelin settings.
Adds spin to rockets
Adds projectile_oil
descr_ui_colour_db.txt
Adds new settings for battle map.
descr_walls.txt
Adds gatehouse settings
Changes all kinds of wall strength settings and missile rates of fire.
export_descr_buildings.txt
Adds gate_defences settin, strength of the boiling_oil.
Changes some trade_fleet settings.
export_descr_units.txt
Adds recruit_priority_offset.
Changes unit stats for nearly every unit in the game.
Not required - These files change some values but have no added fields
descr_battle_map_movement_modifiers.txt
Changes some terrain movement rates.
export_descr_character_traits.txt
Adds Hidden to a few traits.
Adds random_AIBirth1.