Sorry Michael, again I got that wrong. The extrude node was set to "Long"; while the extrusion works as expected in "Union" mode.

However, the issue I have had previously, as it turns out, is not with the maintenance of face normals after separation but rather it seems, a limitation of extrude factory.

If you apply extrude to attached polyhedron (regardless whether separated or not) the extrusions does not conform to face normals, instead they're unidirectional.
I am hoping that the facility to show normals in NodeEditor may be step towards solving this issue.

Sorry again, I should have looked deeper before claiming that the issue was related to surface normals.
Great job with the latest BETA,
James
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