I tried to repro this by going back to an old animation testbed from 4.13, creating a child AnimBlueprint from the original AnimBlueprint in the Animation Starter pack and changing animations in the Asset Override Editor.
I changed the player character to the child AnimBlueprint then updated the project to UE4.15. It played in Editor correctly, so I packaged it for Windows 64 where it continued to work as expected. If this is not an accurate representation of how to reproduce the isssue, would you be willing to share your project for debugging purposes?
If so, please send a link to your zipped file to me in a Private Message on our . This will not be shared publicly and used for the sole purpose of identifying the bug in order to fix it.
Your cooperation in resolving this issue is greatly appreciated,
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