Polygroups not preserved when exporting back to Blender (second GoZ export)

[MakSon480]

Hi, I’ve run into a problem when working with the addon.

Here’s my workflow:

1. I sculpt a mesh in ZBrush and split it into polygroups.

2. I send it to Blender — the polygroups are correctly imported as vertex groups, each with its own material. Perfect!

3. I make some edits in Blender and send the mesh back to ZBrush. The polygroups are preserved — great.

4. But when I export that same mesh again to Blender, the vertex groups and materials are missing. The mesh imports with no vertex groups at all.

Is this a known issue?
Is there a way to make ZBrush keep the polygroups properly linked to vertex groups when exporting again?

Thanks in advance!