This update is a huge change to how roads blend with terrain. Previously, there was a hardcoded 30 meter blend zone from road edge to raw terrain height. Now, this zone is fully customizable using the new Cross-section tool.

This can cause the terrain around your roads to shift a bit or look a bit different. I've tried my best to mitigate this as much as possible, but it's impossible to do perfectly. 

So please be aware that there could be some changes to your track, this is not necessarily a bug. You should be able to fix it quite easily with the new cross-section tool.
Full changelog below!

Thanks all for the patience and huge support! 
v0.20
- Added new road tool: Cross sections. These now control road width, height, camber and blend zone width.
- Added new replay camera editor tool
- Added terrain brush to undo/redo system.
- Added LODs to existing 3D trees for much better performance
- Added LOD tooling to 3D tree maker tool so you can set LOD distances and decimate % per LOD
- Added ability to multi-select layers in the models tab in the Layers panel and bulk-delete
- Added area-select tool to models to select multiple models in the scene and bulk-delete
- Added model chunks to the exporter, so if there is alot of 3D models in the scene it will now create several modelsN.kn5 files 
- Added option for adaptive node size (default on, new option in Settings popup->Editor settings)
- Added toggles for object types  in Settings popup that are influenced by automatic Y updates after road edits
- Added road decals to automatic Y updates after road edits
- Added moveDecal tool  
- Added "Reset timing gates" functionality
- Added double-click to zoom-to-area functionality in default select tool. 
- Added "Mask" texture type to Simple DDS Converter tool
- Added "Remove physics road" button to remove physics road from a road
- Added "Texture wraparound" toggle for some wall types
- Changed start/pit positions car model to a lower poly model
- Changed max sign width/height in the Sign Maker tool to 40 meters, max pole radius to 1 meter
- Changed some values in Noise labs to display in centimeters instead of meters
- Changed default LOD out value from 10km to 1.8km
- Changed default road spline system to Bezier handles
- Changed max terrain size to 40km x 40km (override with satellite imports still possible) 
- Improved speed of road edits like changing width/camber (speed up for adding nodes, deleting nodes coming soon)
- Improved exporter memory usage
- Improved exporter texture cache usage 
- Improved editor memory usage 
- Improved topology of tight corners to prevent mesh overlap and folding 
- Removed shoulder shape settings (berms and ditches) because these are now controlled by cross sections. Unfortunatly could not automatically migrate these to cross sections, so these are lost; apologies! 
- Removed shoulder point setting from asphalt/sand surfaces, this is now controlled by Terrain Blend Reach setting.
- Fixed a bug where some layers were still right-click-deletable when layer is locked. 
- Fixed a mipmap bug with custom textures for walls
- Fixed a bug with export errors for tracks with lots of crowds 
- Fixed a bug where camera keeps moving forward when exiting drive mode
- Fixed a bug with barriers showing the backside of the rail part
- Fixed a bug with tree walls not showing up 
- Fixed a bug with texture_0.dds export errors 
- Fixed a bug with tire marks sometimes not getting the correct shader

And older changelogs:
v0.184

  • Implemented first version of model walls. Select "Model wall" as wall type, select model, draw wall. Can rotate the model, adjust spacing & scale
  • Fixed bug with trace image function not keeping image aspect ratio
  • Fixed bug for custom road textures with rainFX
  • Fixed bugs with deleting sidewalks

v0.1841

  • Fixed a bug in material creator for creating custom road textures
  • Fixed bug with hip building roofs
  • Fixed bugs with lock layer not locking some functionalities
  • Hardened texture checks before export
  • Fixed some local save -> cloud save bugs
  • Fixed cloud saves getting stuck

v0.185

  • Added a "Recenter terrain" button in the top toolbar, in the dropdown menu next to the "Terrain" toggle.
  • Added ability to restore editor UI when it crashes (Chrome translate related)
  • Added normalization for weird characters in track names to prevent crashes in AC
  • Added wall texture tile controls for horizontal and vertical tiling
  • Added vertical offset for signs with single poles in sign maker tool
  • Locked layers are now excluded from y position updates
  • Set maximum wall height to 20m
  • Increased default offset for Left / Right markers for timing gates and start/finish gates
  • Fixed bug with tapered walls having the wrong settings on load
  • Fixed a bug with deleting Cliffs
  • Implemented undo/redo system in free version

v0.186

  • Added custom tire mark splines (subtool of road tool) so tire marks can be drawn anywhere
  • Added moveTiremark tool and added tiremarks to layer panel
  • Added random rotation amount setting and random 180 degrees rotation setting to model walls
  • Added ability to duplicate a model + transforms when in moveModel mode (press Spacebar when model is selected)
  • Added controls for clouds in settings popup in atmosphere mode
  • Disabled god rays in atmosphere mode because it was causing issues
  • Fixed some performance leaks, more to come
  • Fixed bug where custom signs have a black fade at distance
  • Fixed bug with model walls overlapping models
  • Fixed bug with moveBuilding gizmo also rotating camera

v0.187

  • Rewrite of exporter to allow for larger tracks, more models & fix missing (black) texture bug
  • Added support for ksGrass shader to exporter
  • Added ability to edit custom road white lines after placement
  • Added ability to edit tire mark settings after placement
  • Added custom road lines to layer panel
  • Changed tree wall shader to ksGrass
  • Renamed Tire marks layer tab to Splines
  • Fixed some edge case bugs with cloud saves (load track -> delete track -> save track )
  • Fixed bug where local saves didn't include satellite raster image
  • Fixed bug with backups for cloud save assets

v0.188

  • Added "Flatten from first click" to terrain flatten tool so it ignores flatten height setting
  • Added ability to drag AC_TIME_N_L and AC_TIME_N_R poles of timing gates
  • Added bezier handles to wall points in moveWall tool
  • Added collisions to models
  • Added custom water shape tool
  • Added warning when there are missing/deleted assets in the scene
  • Added comments to tracks in /browse/
  • Improved kerb tiling logic in corners
  • Improved kerbs to automatically follow road direction when possible
  • Improved moveSign tool for sticky signs so it snaps to buildings/walls again during move.
  • Improved UV mapping in road branch connections
  • Fixed a bug with map.png and outline.png when atmosphere mode is turned on during export.
  • Fixed bug with toolbar going offscreen when resizing window

v0.1882

  • Fixed missing NULL.dds texture export issue
  • Fixed walls / models not showing on load
  • Fixed misaligned tracks

v0.19

  • Exporter now exports locally by default (if you want to publish your track, toggle on "Upload to cloud")
  • Added Asset bank browser
  • Added multi-texture upload support to model importer
  • Added specular texture support to model importer
  • Added model wall toggle to align model to sloped terrain.
  • Added outer line offset slider to AI line panel
  • Added "Models" and "Signs & props" tab to layer panel, removed "Objects" tab.
  • Added "Models" export layer
  • Added angle info to camber tool
  • Added ctrl + drag to camber tool for more precise control
  • Improved Model importer tool with more strict checks, better UI,
  • Improved road centerline lane system, lane amount setting has been changed to lane width (meters) setting
  • Improved checks for valid models on load of track (too many vertices, missing textures, deleted models)
  • Fixed a bug with cloud saves not allowing saving of track with older cloud URLs
  • Fixed a bug with deleting models through layer panel
  • Fixed bug with placeModel tool not deactivating when popups are open
  • Fixed bug in sign tool that allowed upload of signs without DDS texture
  • Fixed bug with saving 3d trees

v0.1901

  • Disabled some model checks on load of track (older models with > 65k vertices)
  • Disabled model availability check because it contained a bug and marked wrong models as missing

v0.191

  • Added automatic mesh splitting functionality to > 65k vertex meshes in Model Importer tool
  • Improved roadWidth tool to allow road width changes per left/right side
  • Improved moveWall tool for snapped wall points
  • Fixed a bug with sidewalks changing positions during track regeneration and saves/loads

v0.1911

  • Improved roadWidth and roadCamber tools with a faster preview
  • Fixed a bug where non-existing models were not removed from the scene properly and blocked export
  • Fixed a bug with snapped walls not being grounded on terrain
  • Fixed a bug with roadCamber and roadWidth tool being mirrored when road start is a snap.

v0.1916

  • Fixed a bug with road edges blocking exports in some cases
  • Fixed a bug with vertex counts in Model importer tool, on load of track and with mesh-merging during export
  • Fixed a bug with physics road not being included in the export
  • Fixed a bug with roads starting as connection to bridges causing weird behaviour

v0.19161

  • Fixed a bug with roads disappearing

v0.192

  • Added AI line route builder to create fast_lane.ai that spans across multiple roads, junctions etc.
  • Added fast_lane.ai import functionality (WIP)
  • Added "Automatic segment length" toggle for walls, so walls in tight corners get smaller segments
  • Improved the snapped wall system to snap walls across several road connections.
  • Improved fast_lane.ai sideLeft and sideRight so ai line outer edges now follow road edge instead of approximation.
  • Improved fast_lane.ai sideLeft and sideRight handle dragging so it's constrained to the same lateral offset axis used by AC
  • Improved fast_lane.ai data for better AI behaviour in-game
  • Fixed a bug with finish gate texture not loading and blocking export.

v0.1925

  • Implemented new GPXZ API endpoint, so GPXZ now allows for much larger terrain imports
  • Added distance measure tool
  • Improved kerb snap system so it's now possible to snap kerbs to several roads, junctions etc.
  • Improved sidewalk snap system so it's now possible to snap sidewalks to several roads, junctions etc.
  • Added spatial buckets to model merging on export
  • Fixed a bug where "Objects" toggle in top toolbar didn't hide collision wireframes
  • Fixed a bug with Model Importer tool where it counted textures double in some cases

v0.1929

  • Added distance-based culling for models/buildings/props, controlled by a slider in the settings popup in Performance tab (default 300 meters)
  • Fixed a bug with roads disappearing after editing a road.
  • Fixed a bug where heightmap sometimes doesn't load when loading a track
  • Fixed a bug with brake signs not appearing after placement & improved placement logic
  • Fixed a bug where cones are still visible when "Objects" is toggled off in top toolbar