I've got some news (since I know everyone's been just dying for an update): The basic engine is complete! The game is now technically playable - it just isn't likely to be much fun, since there are only three buildings (two of which are useless), two unit types, running out of food or money doesn't actually do anything, etc. But you can claim territory, build cities, improve tiles, build units, and send your armies to fight other players. The links in the OP should link to the new version now.
It's undoubtedly very buggy, so if you find something, please let me know.
Aside from debugging, my next task is to populate the game with content - unit types, resources, buildings, tile improvements, and so on. If anyone has suggestions for them, go ahead and speak up!