Breaking up a complex static mesh

I have a mesh that would be a lot easier to lightmap and texture if it were broken up into sub assemblies with each sub assembly having its own set of UV coordinates and lightmap. But I want the mesh as a whole treated as a single unit in the game/editor rather than having to deal with a bunch of parts. Is this possible? (Using Blender.)

Not sure if it is possible in Blender but a quick workaround would be to import the individual parts as separate meshes with their own UV co-ordinates and lightmaps and then assemble them in an Actor Blueprint.

You would than place the Blueprint in the level and not the meshes. The only disadvantage you might have here is you wouldn’t be able to use Instanced Static Meshes … so if you need thousands of these you could take a performance hit.

I hope i get you right.
For example standard cube.
Select some faces, press strg+p to make a seperate object out of them.
In object mode select both parts and press Strg+G for grouping (name it cubegroup) and whole group selected, while export.
Select the group through the outliner(switch it to groups), before export.
Inside ue4 you import cubegroup.fbx
Edit: It is important for easy use(inside UE4), to use different named materials for each part.
With that you can seperate whatever you whant.