How to export segments as *multimaterial* model in SegmentMesher extension?

We have 4 segments of the cerebrum. When we export them as a model, it works, but it exports as a single material model (where the four segments get fused into one large mesh).

But we want to export it as a multimaterial model, where each segment can be specified to have a different material/color. It is possible to do this in 3D Slicer.

Alternatively, is it possible to export our four segments into four separate single material models, and then somehow combine them together correctly as a single multimaterial model?

Many thanks in advance!

If you use “Cleaver” meshing method then you get a multimaterial model in the .vtk//vtu file. Material of each element is specified in the cell array called label.