This is more of an FYI but I figure it might help someone - either having the same issue or you identify it as a symptom with some related issue.
In Blueprints, I usually create a dynamic material instance once and save it in a variable for future use, but for some reason (probably feeling lazy that day) for one thing I started creating the DMI every frame. Weirdly any morphing I then did on the mesh had no effect. Changing it to set a DMI variable and using that instead fixed it.
I’m guessing creating a DMI on a mesh clears the morphs as morphs are material-based? If so I’m guessing this isn’t considered a bug
I’ve tested under Windows and on a Nexus 9 tablet and get the same behaviour.
Hope that’s of some use!
Cheers,
Tom Macneil