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Augh. My party members seem bound and determined to step on spike traps.

I see the traps. The party sees the traps. They're highlighted 'hey, trap here!'

And yet, when combat starts, these dumb schmucks run right over them to get to the enemy.

The only 'fix' I've found is to turn off AI, but that means micromanaging everything.
This was a problem with Pillars of Eternity too; my party would continue their pathing right through a multitude of traps, getting themselves killed.
Just let your enemies trigger the traps. They do it too.
M4xw0lf: Just let your enemies trigger the traps. They do it too.
Alternative would be to disarm them before initiating combat. I, however, with my less-than-perfect eyesight, do wish the designers would have highlighted the traps ala POE.

Insofar as the AI, I shut if off as soon as I realized my characters were attacking whomever they pleased. I'd rather micro-manage than use some unknown person's sense of tactics