Fixup of spawnables from 5.4 to 5.5 loses custom track names

zComponent - Archive - Feb 5, 2025

In the process of upgrading from 5.4 to 5.5. One of our systems relies on the internal track names in the sequence to dynamically find an actor to bind the track to. As I was testing the system in ...

5.5 Static Mesh Import Pipeline Regression

UE - Editor - Open File Formats - Import and Export - Apr 25, 2025

This question was created in reference to: [Link Removed] This post references the first post because this problem was not discovered till now. I think it was masked because the issue appears to be ...

FBX interchange reimport bug 5.7 -> 5.8

UE - Editor - Open File Formats - Oct 16, 2026

This is a related bug to this interchange fbx one [Link Removed] that is also triggered by reimporting a 5.7 mesh in 5.8 It looks like the asset import data has a property called `node_unique_id` ...

(GAS) Block tags are ignored in version 5.5.2 if two abilities share the same parent tags structure.

UE - Gameplay - Gameplay Ability System - Feb 5, 2025

Block tags are not working correctly in version 5.5.2, it was working in 5.5.1. This is caused by a change done in version 5.5.2. The exact CL is: CL 35930696 ...

Copying a copied 5.0 project into 5.1 does not rename project folder as expected

UE - Editor - Nov 21, 2022

I was able to reproduce this issue 4/4 times, and initially started in version 4.26 to determine if this issue was a regression or not. When copying a 4.27 copied project into 5.0 or 5.1, the 4.27 w ...

CitySample - Level MassCrowd - interactions with SmartObjects/ContextualAnimScene is broken in 5.5

UE - AI - Apr 9, 2025

The 5.5 version of the CitySample project, particularly the MassCrowd scene, was not properly maintained. The previously working functionality of NPCs being able to sit on a bench is now broken. CAS ...

Migration from 4.12.5 to 4.13 can result in Blueprint functions losing input/ouput variables

UE - Gameplay - Blueprint - Sep 5, 2016

When migrating project from 4.12.5 to 4.13, Blueprint functions can lose input/output variable links. ...

FASTBuild cannot compile 5.5 for Windows.

UE - Core - Cpp Tools - UnrealBuildTool - Oct 8, 2024

A licensee reported errors related to the sarif file when compiling version 5.5 using FASTBuild. The problem is that the FB implementation code doesn't know how to deal with the /experimental cl.exe ...

LocalHeightFog placed in 5.3 projects are invalid and not appearing when the project is updated to 5.4

UE - Rendering - Features - May 24, 2024

LocalHeightFog actors placed in levels for 5.3 projects are invalid and not appearing in levels after the project is upgraded to 5.4. This is likely due to LocalHeightFog being renamed to LocalFogVo ...

Translucency Volume are not correctly shadowed in 5.5 without Virtual Shadow Maps and are not light correctly by some lights

UE - Rendering - Features - Dec 20, 2024

TranslucencyVolume spheres are not correctly shadowed nor lit in Unreal 5.5 with VSMs disabled. Unreal 5.4 does correctly shade the sphere without VSMs. There appears to be differences in the outpu ...