I've installed and appears to be working quite well...

However, I keep getting New User email alerts, but does not look like they are actually registered (ie. they do not show up when searching new user registrations within the last 24 hrs?)... Ideas?

That message doesn't look like the one sent by this mod. I guess you could have customized the phrase. But IIRC (it's been quite a while since I looked at the code for this), email is sent when a registration is blocked, not when a new user joins. Maybe you have some other mod that's sending that email? In that case I suppose it's possible that the other mods sends he email before this mod rejects the registration.

Interesting that immediately as soon as I installed this, I received six alerts in a row from bots.

Does this hack override my Human Verification math questions that I have already in place?

It was like raising the red flag to the bull.

Prior to this, I've been getting one or two a day from the ghijklmnop Koreans or Japan.

Mod disabled for now!

No, this does not override any settings or mods. :)

It could have been a coincidence, but it got my attention. I'll try it again later.

Well right after installing the mod, you had six auto bots try and register. By geting alerted that means the mod is working.

But now with it disabled, no bots. There was definitely a rat in the woodpile.

Right, you are not going to get any alerts that a bot is trying to register with the mod disabled.

Nonsense. They've always been there, you simply weren't aware of them until now.

This mod doesn't "attract bots."

Exactly. :)