Body Setup of a Static Mesh with Simple Collision will pass validation, but removing it and using only a Complex collision and setting Collision Complexity "Use Complex as Simple" will fail validation: "Bone None requires at least one collision shape".

UE - Simulation - Gameplay - Oct 20, 2025

Context: By default, Unreal Engine creates both simple and complex shapes, then, based on what the user wants (complex query versus simple query), the physics solver will use the corresponding shape ...

Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds

UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025

We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...

Inconsistent Nanite raster bin debug visualisation colors

UE - Graphics Features - Nanite - Oct 20, 2025

The raster bin debug colors are not always consistent when a static mesh and spline mesh are present ...

In the GameUserSettings class, Landscape quality is not taken into account by GetOverallScalabilityLevel, but is changed by SetOverallScalabilityLevel.

UE - Gameplay - Oct 17, 2025

Context: GameUserSettings stores user settings for a game, for example graphics and sound settings. The Scalability settings provide a way for to adjust the quality of various features in order to m ...

Mutable - morph does not work for a skinned mesh with more than one uv channel

UE - Anim - Mutable - Oct 16, 2025

The morph functionality fails to change when the skinned mesh contains more than one UV channel in a Customizable Object. ...

Curve Debugger window is broken when viewing curves in the Anim Sequence editor

UE - Anim - Runtime - Oct 15, 2025

The curve debugger is currently broken when viewing curves on anim sequences. It seems that only metadata/skeleton curves are displayed, and those aren't updating correctly or showing their type (m ...

[Interchange] FBX - Front Facing X-Axis and Flipped Bone Orientation During Animation

UE - Anim - Runtime - Oct 15, 2025

Actors attached to a skeleton imported through a FBX file with the Front Facing X-Axis option enabled are flipped when the skeleton is animated. ...

Intermittent Content is Missing from Cook errors for objects with Niagara packages

UE - Niagara - Oct 15, 2025

Intermittently when cooking large licensee projects, an error is reported at the end of the cook:LogCook: Error: Content is missing from cook. Source package referenced an object in target package b ...

Smart Link inactive by default when NavLink is a ChildActor

UE - AI - Navigation - Oct 14, 2025

When placing a NavLinkProxy in ChildActor, the link is not enabled by default. In this situation, setting SetSmartLinkEnabled to true does not establish the connection. You must first set it to fal ...

Lightmass CalculatePointShadowing regression in UE5.6

UE - Graphics Features - Oct 14, 2025

There is a regression or change in the Build Lighting process when using Lightmass in Unreal Engine 5.6:When building lighting with Lightmass calling the CalculatePointShadowing function, the result ...