Unreal Engine Issues
Unreal Engine Issues
Merging actors with two-sided materials produces incorrect results
UE - World Creation - Worldbuilding Tools - Merge Actor - Feb 24, 2020Merging two actors using a two-sided material produce incorrect results. Notes: Tested with "Allow two-sided material" on and off, the same result is produced. The same issue can be seen when ge ...
Color picker does not change the color of a Vector Parameter in a Material Instance until the mouse button is released
UE - Graphics Features - Mar 11, 2020This is a regression from 4.23.1 (CL-9631420). The color picker does not update in realtime anymore when holding down the left-mouse button. Only on mouse-release does it update. This was reported ...
Exporting a UE4 Animation into Maya results in wrong skin weight
UE - Editor - Content Pipeline - Datasmith - Importer - Apr 21, 2020UE4 Mannequin animations are not exporting/importing correctly into Maya. The right hand is bulkier and the left shoulder is dislocated. This was reported and tested in 4.23.1 (CL-9631420). this w ...
Static lights become stationary after toggling visiblity of level in packaged build
UE - Rendering - Graphics Features - Jun 11, 2025In 5.5, there is a regression with baked lighting where static lights become stationary lights when a level is hidden and then made visible again. This happens in packaged builds and shows up as sta ...
PlayerCollision visualization incorrect on LandscapeSplineMesh when Nanite is enabled
UE - Rendering - Features - Nanite - Dec 3, 2025From licensee: I’ve found an issue with the visualization of PlayerCollisions when using LandscapeSplineMesh with a mesh that has Nanite enabled. The Chaos collisions shown in the Chaos Visual Debu ...
FZipArchiveCompressTest failing to compile in non-editor Development builds
MetaHuman - Jul 28, 2026`ZipArchiveTest.cpp` fails to compile for non-editor targets in Development configuration. `FZipArchiveCompressTest::RunTest` constructs `FZipArchiveReader`, which is editor only, but that section ...
The AND node always calculates all inputs
UE - Gameplay - Blueprint - Nov 5, 2015The AND node always calculates all inputs, even if the first input fails as False. Probably related to [Link Removed] (currently unresolved, but a Select node-specific fix is mentioned in the comme ...
Staging DLC is reportedly broken
UE - Foundation - Cpp Tools - Automation Tool - Dec 16, 2015According to a licensee, StageFiles() is called with ExcludeWildcard that contains a directory name ("Engine/*") and bRecursive=true when building DLC. This is not supported by Directory.GetFiles(). ...
Editor crashes when opening several marketplace assets - Assertion failed: !HasAnyFlags
UE - Gameplay - Blueprint - Jun 22, 2016Editor crashes while attempting to open several marketplace assets. Allar's Generic Shooter Defuse Studios RTS Template JCInventory Frequency: 5/5 Regression (yes) issue (does not) occur in 4.11 ...
Get Class Defaults node disconnects output pins when project upgraded from 4.11 to 4.12
UE - Gameplay - Blueprint - Jun 7, 2016Upgrading a project from 4.11 to 4.12 causes Class Default nodes to disconnect their output pins from other nodes. If the node is reconnected and saved, it will disconnect again when the project is ...