ULevelSequence trying to duplicate a REINST_ class when creating new custom binding in ConvertOldSpawnables()

UE - Framework - Blueprint Compiler - Jul 23, 2025

The assert that we're hitting is:Cannot replace existing object of a different class.  New Object: /Engine/Transient.REINST_BPC_NPC_VFX_C_230 /Game/Maps/[REDACTED]/Levels/[REDACTED]/LevelSequence/ ...

Merge Actors (Simplify) is broken with Substrate Shader Models Node

UE - Rendering - Features - Shading Models - Sep 29, 2025

Substrate Materials cannot be baked when Meshes are merged using the "Simplify" method. All textures except for the normal are reduced to a single black parameter. The normal texture produced does n ...

Niagara: MeshParameterBinding property of the StaticMeshLocation module does not accept binding to parameters of type StaticMesh.

UE - Niagara - Jan 22, 2026

On the details panel of the StaticMeshLocation module, when expanding the dropdown of the MeshParameterBinding property, user parameters of type StaticMesh don't show up (only those of type "Object" ...

Instanced meshes do not accurately use volume light samples when lit in a statically lit scene

UE - Graphics Features - Aug 14, 2015

When using instanced meshes in a Blueprint or in foliage tool the indirect lighting cache will not correctly light these meshes. I've include a sample project with map to demonstrate what the lice ...

Auto Convex collision generation doesn't work in some instances the accuracy setting

UE - Gameplay - Jun 18, 2015

The new auto-convex collision generated (V-HACD) will not work properly with some meshes to generate accurate collision. Using a rounded single piece mesh the accuracy setting will not work at all ...

Adding a node or variable to a component referenced by another actor crashes editor

UE - Gameplay - Blueprint - Aug 3, 2015

If compile is pressed after adding a variable or node to a blueprint component that has a variable referenced within another blueprint actor, the editor immediately crashes. Frequency: 1/1 Crashr ...

While renaming a variable in the Details panel, clicking another variable will rename it instead

UE - Gameplay - Blueprint - Feb 11, 2015

While renaming a variable in the Details panel, clicking another variable will rename it instead. ...

Interface function has the incorrect pin type if referencing self

UE - Gameplay - Blueprint - Sep 1, 2015

Interface function has the incorrect pin type if referencing self User Description: I have an interface that requires an array of its own interfaces as output. I have that array of interface as a ...

MaterialInterface is not exported and therefore it's functions are not accessible

UE - Graphics Features - Jun 9, 2015

MaterialInterface which is a base class for other classes (such as UMaterialInstanceDynamic) is not being exported which causes compiler errors when a user attempts to access the functions of this c ...

Full screen mode when using a laptop with Optimus ignores the gama setting

UE - Graphics Features - Feb 15, 2016

When using full-screen mode on a optimus laptop the gama that is set for the system appears to be ignored and uses the default setting, even if it has been adjusted in Windows display calibration se ...