Chalcolithic

Since you have a fire in the house and only a small hole in each end of the house, didn’t people suffer from smoke inhalation (SE)?

Well, from what we’ve seen we don’t need any more openings for the smoke to get out. The ones in each end creates a draft which makes the smoke rise up to the ceiling and escape easily without allowing any to be disturbing.

Are baking plates, typical for the middle and late Neolithic cultures of western Europe also known from the younger Neolithic (FR)?

Baking plates are known from the Cerny- und Chassey-cultures, the Bourgogne middle-Neolithic and the Michelsberg-culture, ca. 4500-3500 BC). Their use seem to stop abruptly around 3500 BC caused by another way of baking bread. Maybe from this time onward, people used to bake directly on hot ashes, hot stones, pots or the inner walls of furnaces...