Thomas Brown gets his face cut up while reaching into brambles to pick a particularly good horse chestnut for his ongoing "conkers" game with Daniel. In a later scene in Candleford his face is completely clear, but then a subsequent scene shows it all marked up again.
German army issue woolen longjohns would never have been shipped from a Victorian lingerie shop. They would have been sold in mercantile stores or farm catalogs.
When stoking the fire in the new cooker on the first day, a piece of fabric was closed in the door which would have caught fire.