Hi rupertmaesglas,

was correct before. wikimedia_commons=* files have a syntax to be followed as wiki. In this case it should be "wikimedia_commons=File:Glogfach Lead Mine.jpg", not "wikimedia_commons=https://commons.wikimedia.org/wiki/File:Glogfach Lead Mine.jpg"

is the same logic we apply to wikidata (we tag =Q123, not =https://www.wikidata.org/wiki/Q123 and wikipedia (we tag =en:Example, not =https://en.wikipedia.org/wiki/Example) 