New Release: 0 A.D. Alpha 23 “Ken Wood”
play0ad.com
play0ad.com
https://trac.wildfiregames.com/browser/ps/trunk/source?order...
"Hellas" gives you random cutouts of actual Greece landscape.
"Egypt" is just Egypt rebuilt at small scale, including 6 pre-built cities.
"Jebel Barkal" has a pre-built city on it, which dominates the map and occasionally launches attacks against the players.
Splitting the game logic into multiple threads to have at least network related stuff happening in another thread is afaik on the roadmap for the next development cycle.
What we were able to do was put a hack into the path finding code that bailed on one of the loops after X amount of steps. It made complex paths less accurate (clicking units across the map to attack far away) but actually made the game playable. We could actually control our units whereas with the lag it's completely unplayable late game with 3 players and 3 AI.
0ad comes with atlas, its integrated map editor. Maps also support scripting with Javascript and there are already maps included where waves of enemies get spawned (e.g. Danubis or Jebel Barkal), what you'd probably want for tower defense as well.