Add more vertex colour layers when importing fbx

Hello!

I like the possiblity to add vertex colours to my mesh and export the mesh as fbx. The fbx contains the vertex colours and supports multiple vertex colour layers.
I would like to use this technique for saving other information of a vertex (roughness, metallic, …).
In Blender I can add as much as layers as I want and when it’s exported the layers are inside the fbx-file. But UE4 is only reading the first layer and ignores other layers.

Please add the possiblity to import more thanone vertex colour layer.

edit

The source code which only imports the first layer is here
https://github.com/EpicGames/UnrealEngine/blob/master/Engine/Source/Editor/UnrealEd/Private/Fbx/FbxStaticMeshImport.cpp#L351

Any way of adding more vertex layer really simple?