I'm soooo sorry! All good! Works!

Loading mesh from \\VBOXSVR\Poser\Poser\Python\Rendo\pydeltamesh\Data\untitled_blender.obj...
Loaded mesh with 386835 vertices and 383504 faces.
Subdividing for baking...
Subdivided 2 times.
Finding deltas for level 0
Found a total of 24478 deltas for 83 actors.
Subdividing morph for level 1...
Subdividing for baking...
Subdivided 1 times.
Computing vertex normals...
Finding deltas for level 1...
Found 3193 deltas.
Subdividing morph for level 2...
Computing vertex normals...
Finding deltas for level 2...
Found 9408 deltas.
Morph loaded in 23.4530000687 seconds.

Problem was here. I changed Blender from 2.9 to 3. But had not yet adjusted my preferences.

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