TeamVanilla 
NFSMapEditor opens a Most Wanted install, loads the city from TRACKS/L2RA.BUN and streams its 700-odd world sections as you move. Everything it shows is read from the game's own formats, and everything it changes is written back into them, with a .bak of the original made on the first save.
What it edits
| Scenery | Select, move, rotate and scale placed objects with a gizmo, snapping, and undo and redo. Saves patch the stream in place, so it always loads. |
| Races | Races and challenges from the game's vaults, with undo and save. |
| Markers | Position markers: add, delete and retype. |
| Road graph | The AI road network, drawn by traffic class. Moving a node re-fits its curves, lengths and grid, and the chunk is written back byte for byte. |
| Traffic | Road classes and flags, the vehicles in each traffic pattern, pattern zones and no-cop zones, and the traffic events. The Living World preview follows the game's own spawn, lane and speed rules. |
| Trigger zones | Tunnels, overpasses and the other zone types, labelled with the game's own names, drawn and reshaped in the viewport. |
| Breakers | The 37 pursuit breakers, with their speed traps and event scripts linked. |
| World effects | Birds, fog, chimney smoke, fountains and steam, placed from any of the 128 effect classes and drawn as small particle simulations rather than labels. |
| Audio and weather | Audio zones and the reverb table, and the atmosphere: the fog's scattering model and the visual looks graded over it, with a preview. |
It also exports to Wavefront OBJ, keeps a session in a project file without touching the game, and validates a map for broken transforms and out-of-world positions before it saves. MapCLI, its command-line twin, runs the same readers and writers as self-tests: edit, save, reload, compare.
The release is one MapEditor.exe and its libraries; the shaders and data tables are compiled in. Its idea of a city editor comes from KEd, JernejL's map editor for San Andreas.