I dreamt about this game even though I haven't played this game for a while.
I was at the real location King's Cross and found a "Ghost Track", as it labeled it, above Track 13. So I went through there and came out at "0b" which is in a vertical hallway above "0y" (they both had lowercase letters), which I entered and then I started falling through an area with a numbers dotted around that look like track numbers.
When I woke up I thought for a bit too long "Hey, I should try that."