Alpha Clip & Lightmap generate incorrect shadows

I'm still on 4.2.2f so some of this might not still be an issue for 4.3.X and I understand that it may or may not be fixed.

Using the provided Vegetation shader example:

1. Edit shader > Enable Lightmap support > Compile
2. Shader Compile Errors:
   1. Shader error in 'Shader Forge/Examples/ClipAndTransmission': Program 'vert', unexpected #endif (compiling for d3d11) at line 17
3. Edit shader > Disable OpenGL > Compile
4. Shader Compile Warnings:
   1. Shader warning in 'Shader Forge/Examples/ClipAndTransmission': Program 'vert', unexpected #endif (compiling for d3d11) at line 17
   2. Shader warning in 'Shader Forge/Examples/ClipAndTransmission': Program 'vert', implicit truncation of vector type (compiling for d3d11) at line 38
   3. Shader warning in 'Shader Forge/Examples/ClipAndTransmission': GLSL preprocess error: Unmatched #endif at line 132
5. Set object using Vegetation shader and ground shadow will cast on to Static > Bake Lightmap (Single Lightmap)
6. Bake Lightmap Error:
   1. Material doesn't have a texture property '_MainTex'
7. Edit shader > Rename "Diffuse" property to "MainTex" > Compile > Bake Lightmap (Single Lightmap)

At this point, the Lightmap finally bakes without any errors thrown, however the shadow for this object is incorrect as it bakes the asset as if it was entirely opaque instead of alpha clip as seen in the attached image.