So has any one thought about this? Setting a monster as a guard in a populated place.

What exactly is do you mean? The toolset will allow us to place monsters anywhere we want to, and with some scripting you can get the behaviour you want.

I want to post a golem as a guard in front of the castle gate. Instead of guards.

Well it's rather the same thing, isn't it? They go hostile if you want to enter, and that's it. Easily done.

Is it possible to have guards spawn like the flaming fists in BG?

If so, my town will have a hefty town watch.

"Everything" can be scripted ;).

Mollusken, if that NWN engine is somewhat similar to Infinity Engine, then I assure you not everything can be scripted.
But, we'll see I guess...

As for guards, Tal already told you how to make it, and if you wan't something spawned from nowhere, you may set the invisible creature, entrancetrigger or something else to create hostiles if you try to enter.

Just wondered if it could be done. I read that monsters couldnt be scripted as friendly but I guess I was wrong.

The scripting laguage is similar to C, but without pointers or arrays. Many of the things you will want are already built in, eg OnPerception, GetAlignmentGoodEvil etc.
The limitations are more likely to be in your code writing and amount of memory required!

I suppose it is possible. When you aren't sure, just ask it on the Bioware boards, the devoppers will answer. I suppose it is just possible, however I don't think if monsters would be good guards in palace in a town.... I woul dbve kinda strange, but you can an evil person have monsters as guard.... you can also just go for wardogs and human guards in a normal palace....

Can't imagine you can't do that with monsters. As a DM, you could have a very good reason to do so, so it should be scripted just as easily as a human guard.

Make a human guard or whatever and just change the avatar, if you can that is