Sb3utility | Tutorial

| Error | Cause | Solution | |-------|-------|----------| | “Unsupported version” | Game uses a newer archive format | Update SB3Utility to the latest release. | | Texture import fails | Wrong dimensions (not power of two) | Resize to 256x256, 512x512, 1024x1024, etc. | | Mesh looks broken in game | Vertex count changed or normals missing | Do not add/remove vertices; recalc normals in Blender. | | Archive won’t save | File is read-only | Remove read-only attribute from the .unity3d file. | | Missing shaders after modding | Material references broken | Do not change material names; use original shaders. |

| Error Message | Likely Cause | Solution | |---------------|--------------|----------| | MD5 collision detected | You replaced an asset with an identical MD5 (rare) | Use a different file or force a small change (e.g., add a transparent pixel to an image). | | Cannot read project.json | Corrupted ZIP or invalid JSON | Try opening with 7-Zip manually. If you see garbled text, the file is corrupt beyond repair. | | Asset not found in Scratch | You replaced an asset but didn't update references | Go to Tools → Rebuild Asset Index and resave. | | File too large | Sound >10MB or Image >5MB (Scratch limit) | Compress your file outside SB3Utility, then re-import. |

When you launch SB3Utility, you will see: sb3utility tutorial

Before diving into the tutorial, know that an .sb3 file is simply a ZIP archive containing:

SB3Utility exposes this structure directly. When you change a costume here, you are literally replacing the file inside the ZIP. | Error | Cause | Solution | |-------|-------|----------|

If you’ve ever wanted to go beyond the limitations of the standard Scratch editor—whether to inject high-quality custom sounds, import HD vector assets, or fix corrupted project files—you’ve likely stumbled upon the need for SB3Utility. This powerful, open-source tool acts as a surgical scalpel for .sb3 files (Scratch 3.0 project files).

In this comprehensive tutorial, you will learn what SB3Utility is, how to install it, and how to perform advanced operations like batch asset replacement, JSON editing, and project repair. | Error Message | Likely Cause | Solution

Steps:

What else can you edit in JSON?

Warning: Invalid JSON will corrupt your project. Always make a backup before manual editing.