Placed level instance causes "!ActorInstanceGuid.IsValid()" assertion after changing WorldSettingsClass

UE - World Creation - Worldbuilding Tools - Level Instances - Nov 13, 2023

Resaving the level using ResavePackagesCommandlet is a workaround. ...

Masked material using virtual textures covering a decal will result in black pixels

UE - Rendering - Graphics Features - Nanite - Mar 31, 2025

Depth Passes for Masked Materials using Virtual Textures does not work correctly when it is in front of a Nanite Mesh and a Decal, resulting in black artifacts. Also tested on //UE5/Main, CL: 41024 ...

Source control syncing in editor will sometimes not update changes made to assets

Tools - Aug 25, 2015

When using source control and attempting to sync the project, sometimes assets are not updated to the latest changes properly. This causes changes made to those assets later to override previous ch ...

Setting Pressed Sound for Widget Style Doesn't Set the Value

UE - Editor - UI Systems - Nov 6, 2015

Attempting to set the Pressed Sound for Widget Style dynamically never actually sets the sound. When you click the button, you get no pressed sound. However, when setting the Pressed Sound through t ...

'Get Distance Along Spline At Spline Point' Causes Crash

Tools - Jul 28, 2018

User reports that the reason for the crash is that because UpdateSpline is false on the AddSplinePointAtIndex blueprint node, this line is never called [ReparamTable.Points.Reset(NumSegments * Repar ...

The Add node does not update in the Construction Script

UE - Gameplay - Blueprint - Feb 28, 2015

The Add node does not update in the Construction Script. Reproduced in 4.7.1 binary and Main (//depot/UE4/Promotable-CL-2455917) ...

RepNotify variables passed by reference to a function or macro that then change the value of the variable do not trigger the OnRep function on the Server

UE - Networking - Jul 1, 2015

RepNotify variables passed by reference to a function or macro that then change the value of the variable do not trigger the OnRep function on the Server. This is inconsistent with the behavior with ...

Actor with Camera Component UProperty causes ensure when PIE ends if replicating

UE - Networking - Nov 17, 2015

If an Actor with a CameraComponent is set to replicate, ending a PIE session with 2 players will result in an ensure ...

Particle record in the Matinee leads to crash when playing after record.

Tools - Oct 19, 2017

Particle record feature in the matinee seems not properly working in the Editor. When trying to play in the matinee with recorded keys, the Engine will crash with Access violation - code c0000005. ...

Control Rig - Undo doesn't function correctly with proxy and multi bone controls

UE - Anim - Rigging - Control Rig - Oct 26, 2025

Issue from my Technical Animator where the undo operation in Control Rig doesn't work as expected on Proxy Controls. He has recreated the issue using the "Control Rig Samples Pack" and recorded a vi ...