Originally the rail track tiles aren't colored. Did you color them digitally for this pic or are they even colored beforehand for the players? (almost impossible I know)
I am bloody sure it is painted digitally, otherwise they wouldn't have put the markers, however, I must also say that this is bloody awesome idea to make it clear which track is whose and how the railroad network was developed, so I am all for this digital editing, as long as it is noted somewhere in the photo...
But it would be problematic in terms of game play, because by rule the number of each type of tile in the supply is a strict limit. You would have to keep track of how many of each type has been used so far in the game, and disallow any more of that type to be played after the limit has been reached. Doesn't seem worth the trouble to me.
