I did all the action as it was in this guide (http://theindiestone.com/forums/index.php?/topic/16786-how-to-update-your-map-mod-to-include-foraging-and-zombie-respawn/)
But, zombies dont spawn on the map and they rarely spawn in the houses.
I have ZombieSpawnMap.png, objects (nav, farm, forest, etc...), everything is ok...
What is the problem? If need, I will make screenshots.
Thanks. UPDATE: I fixed it. Problem was with ZombieSpawnMap.png, it was at a lower resolution than would be.