Interesting. I suppose curtains weren't much of a thing back then. Much of the original pegged timbers remain, but evidence of wherever the windows were when the place was first lashed together has long since been lost to history and modifications.
Any shutters, I suspect, would more likely be lift in/fall out, on this house. It's grown over the years. The oldest part is the back of what's now the lounge, and it seems to have evolved north and westerly from there. The newest part is the entire front which is probably a couple of hundred years old. Also, it used to be three cottages, then two and for about the last 30 years just one. As a consequence, undertaking almost any work can be quite an adventure.