Also for more context into the problem we are bumping up against when loading older pak files, here is our specific call stack
[Inline Frame] Rivals2.exe!FLinkerTables::Exp(FPackageIndex) Line 165
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Public\UObject\Linker.h(165)
[Inline Frame] Rivals2.exe!FLinkerLoad::ResolveResource(FPackageIndex) Line 4286
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp(4286)
Rivals2.exe!FLinkerLoad::operator<<(UObject * & Object) Line 6166
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp(6166)
Rivals2.exe!FArchiveProxy::operator<<(UObject * & Value) Line 46
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Public\Serialization\ArchiveProxy.h(46)
[Inline Frame] Rivals2.exe!FBinaryArchiveFormatter::Serialize(UObject * &) Line 273
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Public\Serialization\Formatters\BinaryArchiveFormatter.h(273)
[Inline Frame] Rivals2.exe!FStructuredArchiveSlot::operator<<(UObject * &) Line 349
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Public\Serialization\StructuredArchiveSlots.h(349)
Rivals2.exe!FObjectProperty::SerializeItem(FStructuredArchiveSlot Slot, void * Value, const void * Defaults) Line 227
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\UObject\PropertyObject.cpp(227)
[Inline Frame] Rivals2.exe!FUnversionedPropertySerializer::Serialize(FStructuredArchiveSlot) Line 114
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\UnversionedPropertySerialization.cpp(114)
Rivals2.exe!SerializeUnversionedProperties(const UStruct * Struct, FStructuredArchiveSlot Slot, unsigned char * Data, UStruct * DefaultsStruct, unsigned char * DefaultsData) Line 909
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\UnversionedPropertySerialization.cpp(909)
Rivals2.exe!UStruct::SerializeTaggedProperties(FStructuredArchiveSlot Slot, unsigned char * Data, UStruct * DefaultsStruct, unsigned char * Defaults, const UObject * BreakRecursionIfFullyLoad) Line 1328
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp(1328)
Rivals2.exe!UClass::SerializeDefaultObject(UObject * Object, FStructuredArchiveSlot Slot) Line 5583
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp(5583)
Rivals2.exe!UBlueprintGeneratedClass::SerializeDefaultObject(UObject * Object, FStructuredArchiveSlot Slot) Line 735
at D:\Rivals2Snapnet\Engine\Source\Runtime\Engine\Private\BlueprintGeneratedClass.cpp(735)
[Inline Frame] Rivals2.exe!UClass::SerializeDefaultObject(UObject *) Line 3410
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Public\UObject\Class.h(3410)
Rivals2.exe!FAsyncPackage::EventDrivenSerializeExport(int LocalExportIndex) Line 3534
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(3534)
Rivals2.exe!FAsyncPackage::ProcessImportsAndExports_Event() Line 3853
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(3853)
Rivals2.exe!FAsyncPackage::Event_ProcessImportsAndExports() Line 2912
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(2912)
Rivals2.exe!FAsyncLoadingThread::QueueEvent_ProcessImportsAndExports::__l2::<lambda>(FAsyncLoadEventArgs & Args) Line 2689
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(2689)
[Inline Frame] Rivals2.exe!UE::Core::Private::Function::TFunctionRefBase<UE::Core::Private::Function::TFunctionStorage<0>,void __cdecl(FAsyncLoadEventArgs &)>::operator()(FAsyncLoadEventArgs &) Line 555
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Public\Templates\Function.h(555)
[Inline Frame] Rivals2.exe!FAsyncLoadEventQueue::PopAndExecute(FAsyncLoadEventArgs &) Line 108
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoadingThread.h(108)
Rivals2.exe!FAsyncLoadingThread::ProcessAsyncLoading(int & OutPackagesProcessed, bool bUseTimeLimit, bool bUseFullTimeLimit, float TimeLimit, FFlushRequest & FlushRequest) Line 4393
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(4393)
Rivals2.exe!FAsyncLoadingThread::TickAsyncThread(bool bUseTimeLimit, bool bUseFullTimeLimit, double TimeLimit, bool & bDidSomething, FFlushRequest & FlushRequest) Line 5300
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(5300)
Rivals2.exe!FAsyncLoadingThread::Run() Line 5225
at D:\Rivals2Snapnet\Engine\Source\Runtime\CoreUObject\Private\Serialization\AsyncLoading.cpp(5225)
Rivals2.exe!FRunnableThreadWin::Run() Line 149
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp(149)
Rivals2.exe!FRunnableThreadWin::GuardedRun() Line 71
at D:\Rivals2Snapnet\Engine\Source\Runtime\Core\Private\Windows\WindowsRunnableThread.cpp(71)
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