I'm back with the labels and tags questions!
Here is my code:
mb = CreateDocument[Null, ShowCellTags -> True];
In the new document, I create a new cell, add some random code, and select the bracket of the cell. When I then process
SetOptions[NotebookSelection[mb], CellTags -> "tag test",
CellLabel -> "label test"]
I indeed see in the mb notebook the label and the label appear. Good. Now, I process the code (with the same selection: the cell bracket in the notebook mb)
Options[NotebookSelection[mb], {CellLabel, CellTags}]
and I get as output
{CellLabel -> None, CellTags -> "tag test"}.
Why isn't the CellLabel showing up? I can't get my head around this one...
Thanks for all help, as always!