You might want to try the NESS,
http://nwvault.ign.c....Detail&id=3622 it can respawn: placeables, items, or creatures, all from waypoints. It has great documentation to learn from. It can respawn a set time, or a set day, or at dawn, or at dusk, and can also unspawn after a set time as well. The only thing I have found it to lack is spawn on set month.