Even at the very first dreams/slumber of the game, players are instructed to place tiles in an unusual way, not following the grid lines. Since the setup rules of this dream state that you can place the exploration tiles in whatever orientation/space the players choose, we interpreted as we can even place them in-between grid spaces (two tiles having only half of one side adjacent to each other) .
This made the setup really interesting and tricky, but i think it also made reaching the "lights tile" faster/easier.
Did we play this wrong ?
Tiles can be rotated but must still fully occupy a single grid space. See confirmation here: https://www.etherfields-secrets.com/forum/main/comment/5faebe1d1c05510017fe8719
Too bad this hasn't been clarified yet. I also think it should be possible to put the exploration tiles halfway in two spaces, as then the half walls on the tiles make much more sense.