I'm having so much fun with this game so far. Every bit of it is so well thought out and crafted. I don't know where you are on taking feedback as you get closer to launch, but I had a quick thought on the puzzles.
I thought it might help to add a "submit" button to the puzzle. It was a bit vague to put my order into place and then "is that it? wait... nope, okay, maybe... nope, try something else". I think a button to submit your solution and possibly a message would be helpful to have just a bit more feedback on what I am doing right or wrong. Maybe something like "You were only able to accumulate 149 kilos, you need 200 to solve the puzzle. Try again?". I dunno how feasible that is or if it's something you already considered.
Also, while playing I keep thinking back to this article and followup This American Life episode about diplomacy. They ended up sending an actual american diplomat to a diplomacy tournament. A lot of people have probably already seen it, but if you haven't, it's worth a read.
http://grantland.com/features/diplomacy-the-board-game-of-the-alpha-nerds/
http://www.thisamericanlife.org/radio-archives/episode/531/got-your-back