So I was playing with the DrWarp item I edited into my inventory.
(this is a debug item, it lets you go to any map in the game, provided you can figure out what number it is)

So I find out map #5 is Drogen before being burned down in the intro. The only building you can enter is the hero's house, though.
More interesting is map #23, which will warp you outside the pub in Nanai. (#1C will warp you to the dragon shrine). All the soldiers except the one by the item shop should be gone (though I managed to glitch him out of the picture, I can't repeat it). You actually can enter all the buildings.
Though there's not much of interest (the big house in the top left corner is actually glitched, so you'll enter some hallway between the right half of one of the wide houses and one of the small houses) in most of them, the item shop (again, enterable, but I can't repeat how I got that guard to go away) sells Cure x9, and there's Storage! (which'd be good if you had that much money at the beginning of the game. So, Cure is an item to restore all HP. Normally, it costs 2000 GP/piece, but you can buy 9 of them for only 4500, so buy 2 1/4, get the other 6 3/4 free! In the actual game, you can only get them in the two dream towns, you don't have Storage available, and you can't reenter once the plot is done. I believe the other items were just Herb, Herb x9, Antdt, Antdt x9, and I forgot what the last item was.)
More interesting is the pub (can't enter normally because a soldier is sleeping in front of the door).
Inside, it's like the hero's house post-fire, but with the Nanai house tileset. There's a few NPCs inside (repeats of Camlon post-reconstruction?). Most interesting is that there's a jazz tune I don't believe is used in the accessible portion of the game (though BoF's music varies in quality, and this is more on the "...meh..." side). I have a ZST I can get later.