Confirmed with Blender 3.2:
When exporting a rigged model that has some unweighted vertices as FBX, it can happen that SuperBMD will think the model references bones that it can't find in the skeleton. The cause of this is that the mesh with the unweighted vertices appears above the skeleton root bone in the hierarchy internally, causing SuperBMD to wrongly detect the root bone.
Exporting as dae and then converting correctly yields the unweighted vertices error.
Confirmed with Blender 3.2: When exporting a rigged model that has some unweighted vertices as FBX, it can happen that SuperBMD will think the model references bones that it can't find in the skeleton. The cause of this is that the mesh with the unweighted vertices appears above the skeleton root bone in the hierarchy internally, causing SuperBMD to wrongly detect the root bone.
Exporting as dae and then converting correctly yields the unweighted vertices error.