I've done this in two of my missions. It takes a lot of tweaking, but it's easy enough to make a Medieval or Renaissance setting. The new TOS vases and the mess hall bowls (on redshirt) help. There are also a few tables that look ok in those setting.
Additionally, the Vulcan bench (found under buildings) looks pretty good on those sets, as well as the potted fern plant.
Only reason why I know this is because I'm working on something similar for DA Part 3.
The walls are the sides of Vulcan Large Building 01. The floor is from the same building. The sides are broad so it creates an enclosure when you put them together.
The back wall looks like the side of Vulcan Large Building 02 (or 03, I forget). The tables and chairs are either Romulan or Cardassian (thinking Rom... can't quite remember that either lol). Am I close?
Edit: The other possibility is using the Vulcan building outer walls to cover up the "no collision" interior space of another Vulcan building. That, however would require the spawn point to be inside the building itself. Have no idea if that works though.