If you ever play Arktwend, and you see http://morrowind.nexusmods.com/mods/images/28293-5-1259002633.jpg, that's poor John Moonsugar who was driven off the deep end by Morrowind scripting.

I had a simple script for a guard on a prison ship. He's supposed to wait by a timer for 10 seconds, then AITravel past the player's prison cell, when he's near, give a forcegreeting, finish his AITravel, then go back to where he started from. Everything else being the same from one run of the game to the next he would sometimes do this correct behavior, and sometimes he would skip the wait, and travel past the player without giving his forcegreeting. I'm able to make the script robust enough that the dialogue that needs to happen does happen, but the fact that the script has 2 different behaviors really bothers me.

I was just wondering if anyone else has had to deal with scripts that function differently from one run of the game to the next?

The "robustified" script, for the curious, with extra code in states 2,3,4 to handle the bugged behavior:

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I've had scripts behave differently like that, and I have a pet theory, though it's unproven. GetDistance seems to be one of the common ingredients with odd behavior, I sometimes wonder if the graphics animations continue while the script is held up looking for getDistance results, sometimes moving the target beyond the window of range.

I had a script that was supposed to cause an effect hen the PC walked by an activator placed near a door. Like you, I had set the distance to 128 for the trigger, and... It was then possible for the PC to activate the door before ever coming within the scripted range, thus circumventing the script. Fine, I moved the activator farther from the door so the PC had to be within range before they could activate the door. Only... sometimes it worked, and sometimes it didn't.

While 128 should be the equivalent of 5 to 6 feet, in practice, this seems to vary - and vary by quite a bit. The script would fire properly if the PC passed by it, but only if the range was 200 or a little more (I tend to use 256 as the step up from 128). This sometimes resulted in the script triggering a bit earlier than I wanted, but better early than never, eh? I then moved the activator back toward its original position perhaps 50 gu, and it worked well thereafter.

If your guard walks on by, I suspect that as far as the game is concerned, the trigger range is never crossed for one reason or another.

Shoot me now, Arktwend uses GetDistance a lot I previously thought it was very reliable, but something's definitely whacky.

It does sound like we encountered a similar problem. Maybe I should break up his travel into 2 stages.