Unteamed units tend not to want to shoot things. There is an engineer script that makes the unteamed HUMAN shoot at an object that has a target script on it, thinking he is repairing it. You could try using M01 (or M00, not quite sure)_base defence, if you don't want it to move. A more complicated way to get it to move and shoot, (which I used in the Sole Survior Training Mission, it's coming out soon
), is JFW_Gaurd_Duty. You set up a waypath in that for them to follow around and it shoots as it goes along. Could really use a nice helper bone for it though. Anyway, you need the custom script for that, go check out the official forums and ask around where to get them, as I can't recall.
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