WorldPartitionLevelHelper crash game at loading

I´m new to the World Partition topic, and now i´m trying to use world partition in my horror game with help of horror engine.

I started to create a new level in UE5.4.3 and the level uses world partition.

If i start a new game i can play the “first” map without issues. If i solve some puzzles and the game saves it and i try to reload to the last “checkpoint” or last save game the game crashed (independently if in editor or standalone).

Message:
Assertion failed: !FindObject(nullptr, *PackageName) [File:D:\build++UE5\Sync\Engine\Source\Runtime\Engine\Private\WorldPartition\WorldPartitionLevelHelper.cpp] [Line: 354]

I also tried to uncheck the Spatially Loaded for the PlayerStart, but it doesn´t helped me.

I don´t think that the save object is wrong in horror engine, because if i create a new project without world partition, i can save and reload without issues.

Did someone else has the same issue and can help?

Hello, I have the same crash repeatedly.
If I duplicate the problematic level, I can launch the game in PIE once, but if I exit and launch it again, it crashes.
It seems to happen more easily when I place a level instance.
Has anyone managed to work around this?

[2026.05.24-17.36.03:747][ 60]LogWindows: Error: appError called: Assertion failed: !FindObject(nullptr, *PackageName) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\WorldPartition\WorldPartitionLevelHelper.cpp] [Line: 417]

There are a few warnings like below right before this, but I’m not sure if it is related

[2026.05.24-17.36.03:183][ 60]LogStreaming: Warning: LoadPackage: SkipPackage: /Game/Auto/Maps/Levels/RogueLite/UEDPIE_0_NewWorld (0x1223EB574C7DCBBC) - The package to load does not exist on disk or in the loader

[2026.05.24-17.36.03:183][ 60]LogUObjectGlobals: Warning: オブジェクト ‘Object /Game/Auto/Maps/Levels/RogueLite/UEDPIE_0_NewWorld.NewWorld:PersistentLevel.BP_Gamemode_C_0.AC_GameModeEventManager’ が見つかりませんでした


I’ve reproduced this on UE 5.7.4, Windows 11