Zombies will not follow waypoints unless you include the waypoint code from any soldier script. They do not have the animations to walk waypoints with out looking strange. Why they are free roaming characters and there actions are based on range from the player.
Only the soldiers will follow waypoints right now with default scripts.
If you add the waypoint code into your script then they will walk the waypoints, But you will need to do some heavy rewriting of the scripts.
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