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 ...

[CrashReport] UE4Editor_Kismet!SBlueprintEditorSelectedDebugObjectWidget::GenerateDebugObjectNames() [sblueprinteditorselecteddebugobjectwidget.cpp:454]

UE - Gameplay - Blueprint - Dec 9, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...

[CrashReport] UE4Editor_Engine!UAnimMontage::IsValidAdditive() [animmontage.cpp:702]

OLD - Anim - May 19, 2016

Error message: Stack overflow - code c00000fd (first/second chance not available) Source Context: 687 if (SyncGroup != NAME_None) 688 { 689 CollectMarkers(); 690 ...

Incorrect Velocity Calculation at Animation Sequence Transitions in Level Sequence

zComponent - Archive - Feb 18, 2025

When adding an Animation Track to a Level Sequence and placing Animation Sequences back-to-back without gaps, the velocity can be miscalculated at the transition between sequences. This issue occur ...

Undo after disconnecting a target pin will cause a series of internal compile errors

UE - Gameplay - Blueprint - Mar 15, 2016

Undo after disconnecting a target pin will cause a series of internal compile errors User Description: I've run into what I think is a bug when attempting to compile a blueprint after mistakenly b ...

[AI] Bad entries in NavigationRepository for Box collision with bCanEverAffectNavigation set to false

UE - Runtime - Character - Oct 26, 2025

Some components continue to dirty the navigation state even if bCanEverAffectNavigation is unchecked. Behavior appears very similar to an existing bug, UE-251496 ([Link Removed]), which involves a ...

Crash rendering image sequence if the Sub-Level with matinee is not loaded

Tools - Apr 15, 2016

Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...

Saving Behavior Tree with Blueprint task inheriting from native class invalidates Blackboard key when BP contains a function

UE - AI - Jul 8, 2025

A regression introduced in UE 5.6 causes Blackboard key selectors in Blueprint tasks to become invalid when the Blueprint inherits from a native subclass of UBTTask_MoveTo (or UBTTask_BlackboardBase ...

[CrashReport] Assertion failed: !bRequireNormalization - UE4Editor_Landscape!ULandscapeComponent::ReplaceLayer()

UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017

This is a common crash affecting users in 4.16, and has occurred since at least 4.14. Over 200 unique users have been affected, though they have provided little information. User DescriptionsI am a ...

Sub-world partitions do not properly handle partial editor loading as world partition standalone level instances' spatially loaded actors do not get loaded even when the Level Instance is force loaded or loaded in by region.

UE - World Creation - Worldbuilding Tools - World Partition - Aug 19, 2025

Context Level Instancing is a level-based workflow designed to improve and streamline the level editing experience. In a standalone Level Behavior, when the Level Instance Actor is loaded through it ...