And the common +12V, I tend to read what is there and if it is not a blatant obvious mistake I don't presume. As stated in post #3 he wants to run a track, now without more information we can only presume, so I answered the questions directly.
Again it is interesting to see how wide the misunderstanding is regarding inner layers and creepage and clearance distances, I see all sorts of views from engineers from half the quoted distances to full quoted differences to everything in between to some that even get the distance correct for inner layers.