Mesh modeled in Modo is correct and is behaving correctly.
When imported into PopcornFX, it looks ok, both in mesh view and particle editor.
If the same mesh is directly imported into Unity it also looks ok.
BUT, if the mesh is a particle in an effect and that effect is baked, it's normals are flipped when baked into Unity.
This only occurs with PopcornFX Settings> Before Image Effect.
Windows 10 64bit, PopcornFX 1.9.2, updated to 1.9.3. still same problem.