Packed Level Actors will create ISMs with inverted normals when a portion of static meshes have negative scales. This is apparent with two-sided materials.

Packed level actors will create ISM instances with inverted normals when the selection of meshes used to create the packed level actor contains a subset of meshes with negative scales.

This is the same issue as reported in this other case: https://udn.unrealengine.com/s/question/0D5QP000007sIUW0A2/wrong-world-normals-when-using-two-sided-material, although the instances were created by PCG in this case, vs the packed level actor system.

The previously provided fix involves disabling bReverseCulling on the ISM component and then negating the scale of the entire component, instead of a per instance basis.

• In a new project, add some static meshes, e.g. cubes to a level
• Apply a two-sided material to some of the cubes, e.g. M_Bush from the Starter Content
• Select the meshes in the world outliner and convert them to a Packed Level Actor
• Observe how two of the meshes now appear to have inverted normals, e.g. black leaves when using M_Bush