Parameter distributions can be reset to None in Cascade Particle Systems, causing Cascade to Niagara conversion to crash the editor.

UE - Rendering - Architecture - Niagara - Apr 18, 2022

Cascade to Niagara conversion causes the editor to crash due to any distribution parameter in the Particle Emitter being reset to none. Repro Rate: 4/4 Tested this in //UE4/Release-4.27 @ CL# 1831 ...

Crash Occurs In Skeletal Mesh Editor When Adding a Bone Transform in a New Animation Sequence

UE - Runtime - Animation - Apr 22, 2022

Occurs 3/3 times Regression does occur: tested in //UE4/Release-4.27.2  EGL Live @ CL 18319896. No crash occurred.  A crash occurs in the Skeletal Mesh Editor when adding a bone transform to the A ...

Sequencer Frames Render Black When Four or Less Frames Are Rendered

zComponent - Archive - Apr 22, 2022

Occurs: 5/5 times **MRQ renders black frames when custom playback range is set to four frames or less. Regression does not occur: tested using //UE4/Release-4.27 @ CL 18429761 GH Note: Issue does ...

Child Actor Components are visible in editor but disappears while playing or simulating.

UE - Framework - Components - Apr 25, 2022

Child Actor Components are visible in editor but disappear while playing or simulating. On BP_Cube_Row, setting 'Hidden in Game' to true then false during play will make the object appear. Repro Ra ...

Suspend/resume iOS Metal Crash on low end device with MTLCommandBufferErrorMemoryless error with lots of geometry

UE - Platform - Mobile - Systems - May 11, 2023

The project was built in Unreal 4.27.2 binary from the Epic Games Launcher. At this stage we have only observed the crash on devices with a hardware combination of Apple A9 1.8 GHz and 2GB of Memory ...

[MetaSounds] The Members' detail panel does not accurately update after making an edit and selecting a different member

UE - Audio - MetaSounds - Jun 26, 2023

Note: This issue also affects MetaSound Patches and any Members Menu List Repro Rate: 5/5 Regression marked as No: issue was seen in 5.2 and 5.1  UE5+Release-5.2-CL-26001984 UE5+Release-5.1-CL- ...

Unable to play replays with custom GameNetworkProtocolVersion set at runtime

UE - Framework - Networking - Sep 20, 2023

It seems that when comparing the custom versions for a replay (in the "operator<<" defined in ReplayTypes.cpp), the value retrieved from the FCurrentCustomVersions is not the value set at runtime, b ...

SKP import - Materials missing and incorrect when using Collapse all

TM - Interoperability - Sep 30, 2026

Reported in SF [Link Removed] When importing a .skp model into Twinmotion 2026.2 Preview as Geoemtry, using the Collapse all mode will cause materials to be displayed incorrectly, replacing most ma ...

Widget Component Does Not Cast Shadows From Certain Lights

UE - Editor - UI Systems - Oct 19, 2016

The widget component acts differently under different lighting types. For example it will cast a shadow if being lit by a directional light but won't otherwise. It also seems point lights affect t ...

Hang and log spam when making changes to a landscape material with the landscape editor open

UE - LD & Modeling - Terrain - Landscape - Jul 25, 2016

Editor hangs if changes are made to the material which is currently assigned to a landscape while the landscape editor is open. Also spams "LogMaterial: 0.03 seconds spent updating 1 materials, 1 i ...