Thanks CD, I thought you might like it
I am pretty impressed with how well it works, myself.
I was thinking again about putting something like this into the source, and I think it might be fairly easy. Instead of adding more stuff to NPC settings, I think it makes more sense to just add a command that will automatically create a roambox around an NPC spawn point based on Max X and Y variances from the spawn point. So, you would just target the NPC you want to add a roambox for and type something like "#autoroambox 100 100", and that would set it to update the database for that spawn group to use a roam box with a 100 variance for X and Y.
Unless anyone objects, I can probably just add LoS and Z checks into the roam box code. I don't see any reason not to add it. I haven't really looked into the roam box code much yet, so it might already do it as far as I know, but I doubt it.