The directory string shuto_revival_project_beta/main_layout represents the foundational infrastructure for one of the most significant modifications in sim-racing history: the Shutoko Revival Project (SRP). This mod transforms Assetto Corsa into a hyper-realistic simulation of Tokyo's Metropolitan Expressway. However, for many users, this specific string is encountered not as a feature, but as a frustrating error message—usually stating that the track is missing or the layout cannot be found.

To resolve this immediately: the folder in your content/tracks/ directory must be named exactly shuto_revival_project_beta. Any suffix, such as _ptb or version numbers like _0.9.1, will break the link to the main_layout configuration required by most online servers.

Understanding the Evolution of the Main Layout

The "Main Layout" is the definitive configuration of the Shutoko map. In previous iterations of the mod, specifically versions prior to 0.9.3, this specific road network was frequently referred to as the "Overload Layout." The developers renamed it to "Main Layout" to streamline server synchronization and clear up confusion between various testing builds.

If a server requires shuto_revival_project_beta/main_layout, it is looking for a specific set of physics files, spline data, and visual models contained within that specific folder structure. The transition from "Overload" to "Main" wasn't just a name change; it involved a massive optimization of the 170 pit boxes and the integration of a unified highway system including the C1 Loop, the Bayshore Route (Wangan), and the Yokohane line.

Proper Installation and Directory Architecture

The most common reason for the "Track Not Found" error is an incorrect installation path. Assetto Corsa is highly sensitive to folder naming conventions because the models_main_layout.ini and other configuration files rely on relative paths.

Correct Folder Structure

Your installation must mirror this exact hierarchy: [Steam Library Folder]\steamapps\common\assettocorsa\content\tracks\shuto_revival_project_beta\

Inside this folder, you should see the following subdirectories:

  • ui: Contains the user interface images and descriptions.
  • data: Holds the physics and surface definitions.
  • main_layout: This specific folder contains the .kn5 models and the map.png specific to the main highway loop.
  • ai: (Optional but recommended) Contains the fast_lane.ai files for traffic simulation.

If your folder is named SRP_v0.9.3_Main, the Content Manager (CM) and the game engine will fail to recognize the main_layout when you attempt to join a server, resulting in a disconnection.

Troubleshooting the "Missing Layout" and Checksum Errors

Even with the correct folder name, users often face secondary issues that prevent the main_layout from loading properly.

The Checksum Mismatch

Online servers use checksums to ensure all players are using the same track physics to prevent cheating or desync. If you receive a "Checksum Failed" error:

  1. Surfaces.ini Conflict: Ensure you haven't manually modified the surfaces.ini file in the data folder.
  2. Version Mismatch: Many servers have migrated to SRP 0.9.3. If you are still running 0.9.1 or 0.9.2 PTB (Public Testing Build), the models.ini will differ, triggering a checksum error.
  3. Data.acd: If the server uses a protected data file, ensure your data folder hasn't been unpacked or altered.

Stuck on "Initialising AI Spline"

A common bug when loading the main_layout is the game hanging during the "Initialising AI Spline" phase. This happens because the game is attempting to load a single-player AI spline that might be corrupted or incompatible with a free-roam server.

  • The Fix: Navigate to content/tracks/shuto_revival_project_beta/main_layout/ai/. Rename the ai folder to ai_off. This forces the game to ignore the local spline and use the server-provided traffic data, allowing for a much faster load time.

Server-Side Configuration and Pit Indices

If you are setting up a server for shuto_revival_project_beta/main_layout, understanding the pit index system is crucial for managing where players spawn on the massive map. The "Main Layout" integrates multiple Parking Areas (PAs) into a single map, and the spawn location is determined by the [CAR_X] index in your entry_list.ini.

Spawn Location Mapping

Based on technical specifications of the 0.9.3 build:

  • Tatsumi PA: Indices [CAR_0] to [CAR_39]. This is the most popular starting point for C1 Loop runs.
  • Yoyogi PA: Indices [CAR_40] to [CAR_61].
  • Heiwajima PA (Northbound): Indices [CAR_62] to [CAR_81].
  • Heiwajima PA (Southbound): Indices [CAR_82] to [CAR_157].
  • Daishi PA: Indices [CAR_158] to [CAR_169].

If you want your players to spawn at a specific location, you must assign their car to the corresponding index. You cannot have duplicate indices or skip numbers, as the Assetto Server engine requires a sequential list to initialize the main_layout physics.

Optimizing Performance for the Shutoko Mod

The main_layout is exceptionally resource-intensive. It features thousands of light sources and a massive draw distance. To maintain a stable 60 FPS (or higher for VR users), certain configurations within the Custom Shaders Patch (CSP) are necessary.

Recommended CSP Settings

  1. Track Adjustments: Enable "Larger tracks support" in CSP settings. The Shutoko map exceeds the standard Kunos size limits.
  2. Grass FX: Disable this for SRP. Since the track is almost entirely asphalt and concrete, keeping Grass FX active only wastes CPU cycles.
  3. Lighting FX: Set "Dynamic Lights" to a reasonable range. In the main_layout, having hundreds of headlights rendered at once can crush GPU performance.
  4. Weather FX: If using Pure or Sol, ensure your CSP version is at least 0.1.79. Older versions may cause the sky to flicker or the road textures to appear black on the main_layout.

The Role of Traffic in the Main Layout

The true essence of SRP is navigating through heavy "Shuto" traffic. This is achieved through the assetto-server AI spline system. Unlike standard racing tracks, the main_layout traffic doesn't follow a race line; it follows a "fast_lane" that spans the entire expressway.

To achieve dense traffic without crashing the server:

  • Spawn Distance: In your extra_cfg.yml, set the MinSpawnDistance to approximately 100 meters and MaxSpawnDistance to 800 meters.
  • AI Safety: Setting MinAISafetyDistance too low (below 12 meters) will cause the AI to panic-brake, creating massive pile-ups on the Wangan straight.
  • Despawn Logic: Ensure AI cars despawn once they are 1000 meters behind the player to free up system resources for new cars spawning ahead.

Conclusion

The shuto_revival_project_beta/main_layout is the gateway to the most immersive street-driving experience available in gaming today. While the folder naming issues and checksum errors can be a hurdle for new players, they are easily solved by adhering to the strict directory naming convention: shuto_revival_project_beta. By ensuring your installation is clean, your CSP is updated, and your folder names are exact, you can transition from troubleshooting to cruising the neon-lit streets of Tokyo in minutes.

FAQ

Why is my map invisible in the Main Layout?

This usually happens if the .kn5 files are in the wrong subfolder. Ensure the shuto_revival_project_beta/main_layout folder contains the actual track model files and not just another subfolder.

Can I use the Main Layout without Content Manager?

Technically yes, but it is not recommended. The standard Kunos launcher struggles to parse the complex layout structures of SRP. Content Manager is essential for correctly identifying the main_layout and its associated CSP extensions.

How do I fix the "Track Params" error?

If the server logs show "Missing track params," you can manually add the coordinates for Tokyo to your data_track_params.ini. Use Latitude 35.6704 and Longitude 139.7408, with the timezone set to Asia/Tokyo. Alternatively, set force_server_track_params: true in your server configuration.

What happened to the Overload Layout?

It was officially retired and merged into the main_layout. If a server still asks for "Overload," that server is running an obsolete version of the mod and should be updated to SRP 0.9.3 or later for security and performance reasons.

Does the Main Layout support rain?

Yes, provided you have the Patreon version of CSP (Preview builds) and a weather script like Pure. The main_layout includes specific "Rain FX" markers that allow puddles to form dynamically in the low-lying areas of the expressway.