Things that must be every time the level is loaded:
*Delete all terrain
*Place the terrain:
-Terrain->_Metroid->Metroid_Level
-Terrain->_Metroid->Metroid_Terrain_Replaements_And_Additions

Do before every save
*Discard vis data
*Repartition vis data
*Run manual vis points.
*Regen lighting

Do before every export (if the level was opened)
*Set the cinematic collision mode of Tile->_Metroid->Mine_Elevator->Mine_Elevator_Kill_Zone to Kill
*Save
*Export

Do before every pathgen:
*Select all the simple objects named Trooper_Crate; copy, paste, and replace them with Tile->_Metroid->Crate_Pathfind_Blocker2
*Select all the simple objects named Explosive_Rigged_Trooper_Crate; copy, paste, and replace them with Tile->_Metroid->Crate_Pathfind_Blocker
*Select all the spawner objects named Random_Weapon_Crate_Spawner; copy, paste, and replace them with Tile->_Metroid->Crate_Pathfind_Blocker
*Select all the vehicle objects named Troop_Crate_Physics; copy, paste, and replace them with Tile->_Metroid->Crate_Pathfind_Blocker
*Place the terrain object Terrain->_Metroid->Temporary_Pathfind_Blocker

Do After every pathgen
*Delete the terrain object Temporary_Pathfind_Blocker
*Delete all tiles named Crate_Pathfind_Blocker and Crate_Pathfind_Blocker2