If an instance of a blueprint is in the scene selecting it and another blueprint and choosing the option to Replace references of the one in scene with the other will cause Critical Failure errors. Further errors are generated is the blueprint being replaced is the parent of the replacing blueprint
1. Launch UE4 Editor (any project)
2. Create blueprint based on actor (BaseBP)
3. Add an instance of BaseBP to the scene
4. Create a second blueprint based on actor (ReplacementBP)
5. Select both blueprints in the content browser
6. Right click either blueprint and select Asset Actions -> Replace References
7. Choose ReplacementBP as the asset to consolodtate
Result:
Critical Failure window appears after selecting Consolidate Assets
Note:
Further errors appear before the Critical Failure window if ReplacementBP is a child of BaseBP
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