Scott, I love this tool. I could see us setting up a lap top at the end of the table - or how about having it projected on your wall - or on the ceiling! - for all to see easily. Lots of options here.
Something came to mind as I'm running through all the various scoring options in my mind. At game end the owners of the King and Robber Baron tiles receive points for each completed respective feature. There will be completed features that never got scored (as is the case with many roads and some cities). I believe your attempt at counting the city and road features through the course of the game is unnecessary. You will arrive at an incomplete number and won't know on the board what has been counted and what has not. You will have to physically count all the features at end game to arrive at a total. Sorry if that causes a hiccup for you - hopefully it simplifies something else for you though.
Also, as I'm looking at the interface I realized it would be handy to know what tile count would be needed to win the King or Robber Baron - just like you know what you need for barrels, ribbons, etc. Would it be possible to have a tile count indicator (perhaps overlaid on the king and robber tile, or somewhere adjacent to it) so that any player can know at a glance what tile count won that tile and what is required to steal it?
Great job so far!
(by the way, I could not see Green when I toggled through the color options for each player in the interface. Not sure if I was doing something wrong. Also, could not see any of the non-standard colors.)