Unreal Engine Issues
Unreal Engine Issues
The hierarchy of Actors in LevelInstances can break when using BPs as parent
UE - World Creation - Worldbuilding Tools - Level Instances - Feb 18, 2026The hierarchy of a LevelInstance actors (Outliner) will break when cooking. The source is the call to AActor::RerunConstructionScripts in FWorldPartitionLevelHelper::MoveExternalActorsToLevel. The ...
Instanced Static Mesh components that are part of a Blueprint aren't visible in Standalone Game
UE - Gameplay - Aug 9, 2017Instanced Static Mesh components created through the Construction Script aren't visible in Standalone Game. Collision is still present. They are visible in all other play modes and if created on Eve ...
FCustomPrimitiveDataCustomization::SetVectorColor is closing the colorpicker and only updating the first channel
UE - Graphics Features - Aug 23, 2023When it updates the red channel, the Simple Construction Script (SCS) gets re-run (via AActor::RerunConstructionScripts) on the Blueprint Actor instance generating new instances of all its component ...
Illegal reference to private object when cooking a child level sequence with a time warp track
zComponent - Archive - Apr 28, 2025Slack: [Link Removed] Another Slack: [Link Removed] Cook error:UATHelper: Cooking (Windows): LogSavePackage: Warning: UATHelper: Cooking (Windows): Referencers of MovieSceneTimeWarpSection /Gam ...
AActor::CheckActorComponents has misleading warning
UE - Gameplay - Components - Apr 24, 2023There's actually two issues going on here: 1. The REINST references are incorrect, and due to [Link Removed]. 2. Blueprint created components will always have different names between the instance ...
Spline Mesh Component created from KML file doesn't render in PIE after spline point change
Tools - Oct 8, 2015Spline Mesh Component created from KML file doesn't render in PIE after spline point change I cannot get this to occur outside of the users test project. He is pulling data from a KML file, creatin ...
Color picker widget auto-closes unnecessarily
UE - Editor - Aug 3, 2026A licensee reports that the color picket widget in Unreal Editor closes whenever a blueprint actor (map placed instance of an actor blueprint) receives a property changed event, even if the change e ...
Custom Primitive Data are not (fully) functional with Instanced Static Mesh components
UE - Graphics Features - Mar 29, 2022If the ISM component is not in a blueprint, but added directly inside the level, the CPD works. If the CPD value is set from a construction script through either the Default or Transient function, i ...
Set world or relative rotation on a child component sets the wrong rotation
UE - Gameplay - Blueprint - Aug 21, 2018Unexpected results from setting relative rotation on child of child in BP. Also confirmed in Main CL 4302610 "I have found that changing this code from RelativeRotationCache . RotatorToQuat (NewRe ...
LOD Build Scale set higher than 1 will cause a merged actor to increase to that scale when created
OLD - Anim - Aug 8, 2017LOD Build Scale set higher than 1 will cause a merged actor to increase to that scale when created. It seems to be using the LOD Build Scale to double in size on actor merge. This is a regression: ...