**Hardware limitations**: Toon rendering can be RAM-intensive, and if your system RAM is full, it can cause rendering problems and crashes.
**Cache size limitations**: Insufficient cache size can lead to rendering issues, and expanding the cache size can resolve the problem.
**Software compatibility**: Incompatibility between software versions can cause rendering issues, and updating software can resolve the problem.
**Driver updates**: Outdated graphics drivers can cause rendering issues, and updating drivers can resolve the problem.
**Cache path optimization**: Optimizing cache paths can improve rendering performance and reduce crashes.
**Rendering threads**: Setting rendering threads to the number of CPUs can speed up rendering.
**Bitmap sequence rendering**: Rendering to bitmap sequence can be a workaround for toon rendering issues.
**Toon shader settings**: Incorrect toon shader settings, such as angle and bounce light settings, can cause rendering issues.
**Renderer type**: Using the wrong renderer type, such as Workbench instead of Cycles or Eevee, can cause rendering issues in Blender.
**Object rendering disabled**: Objects can be disabled for rendering, causing them to not appear in the final render.
**Particle system rendering**: Particle systems can be set to not render the emitter, causing rendering issues.
**AutoRender option**: Disabling the AutoRender option can cause rendering issues in Toon Boom Harmony.
**Graphics card limitations**: Insufficient graphics card memory or outdated graphics cards can cause rendering issues.
**Scene complexity**: Complex scenes can cause rendering issues, and optimizing scene complexity can improve rendering performance.
**Lighting settings**: Incorrect lighting settings, such as incorrect sun angle and bounce light settings, can cause rendering issues.
**Shader compatibility**: Incompatibility between shaders and rendering engines can cause rendering issues.
**Bitmap import limitations**: Importing large bitmaps can cause rendering issues, and optimizing bitmap import can improve rendering performance.
**Cache disk space**: Insufficient cache disk space can cause rendering issues, and increasing cache disk space can resolve the problem.
**Rendering resolution**: Rendering at high resolutions can cause rendering issues, and reducing rendering resolution can improve performance.
**CPU and RAM usage**: High CPU and RAM usage can cause rendering issues, and optimizing system resources can improve rendering performance.