I've finished BG1 since then, no other 1-turn attacking mages found in BG1, never had any issues with Bentley.
Can't say for Corneil since that BG1 install is on another ancient drive now (I can access the files but can't run it without some meddling). But in the BG2 install Corneil isn't doing anything fishy and he probably has the script too since I'm still using BP.
If you want to look into anyone, I would suggest 'Ulrien of Cormyr' in Mithrest Inn. He's from some mod I believe but one time he greeted me with a death spell of sorts upon entering. Didn't 1-turn attack me next time though so perhaps it's not the same bug.
There's a bunch of bugs in BG2 as well, granted, but I'll report them sometime after Christmas. Most are minor.
Here's a morsel though:
The weirdest one that might be difficult to debug is enemies going green (ally) in the middle of the battle for some reason. They're not controllable, the hover cursor is the one for conversation. I have only two theories at this moment and neither makes a ton of sense.
a) Talauntin was attacking me as a Pink Dragon when his imp ported me to his realm so I changed him to 'ally' in SK to be able to access the shop. I've made him 'neutral' yesterday after the green bug stroke again and made me think of it. I reversed that change and the bug didn't go away.
b) I have a super slight feeling it might be actually team character scripts causing this for some reason. It was a late night thought and I didn't have time to see if it makes sense, but I don't actually recall it happening when I had AI off, I don't think. But could well be a coincidence.
This is probably the biggest bug I've encountered in BG2 for now, but it's not easily debuggable I fear.
Update-ish thingie: well, really just more "maaaaybe it's related". I thiiink it might have something to do with fights where opponents can charm/dominate the characters? Just a thought, but where I saw it happen for certain was Sirine in sewers, sewer party, some sort of Yuan-ti encounter with spellcasters present and a vampire battle in chapter 3. I reloaded on the vampire battle and turned AI off. No bug then. I wouldn't say it necessarily confirms my suspicions, but it doesn't invalidate them either for now. I'll keep watching.
I haven't seen the bug strike even once throughout the entire Umar Hills quest, De'Arnise keep, Slaver plots, Harpers plot and a bunch of others I'm sure. And I don't think any of these enemies use charm/dominate. Maybe I'm onto something?
Had one crash averted by killing the NPC with CTRL-Y: in Azengaard encounter in Irenicus Dungeon there was a Time Assassin at the bottom of the Oasis map who was crashing my game when I casted a spell on him or when he attacked (hard to say, it happened at once I guess). It crashed like 3-4 times, but when I wanted to check in the console and reloaded the pre-assassin save later it wouldn't crash anymore.
Edited by Munchkin Mooch, 17 December 2015 - 02:09 PM.