Opening the WeapGun or WeapLauncher blueprints will show that Mesh3P has a relative rotation of -90, however both meshes are shown overlapping each other. When an instance of the blueprint is added to the viewport, Mesh3P is rotated -90 degrees from Mesh1P.
No - same behavior occurs in 4.13.2 version of ShooterGame
the instance in the editor viewport shows two meshes rotated 90 degrees from each other.
Both blueprint and editor viewports show the same view for the meshes. Both viewports showing two meshes or both showing only one.
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