I ran the modified gnoll encampment today, for the first time. I noted a few spots within the quest where a spotted trap appeared in the wall, or even the black space beyond the wall. However, you would take damage from it by walking across the floor.

I'm not sure if this is intentional, as in trying to convey a trip wire or such...or just odd trap placements.

I noticed this as well. It's like the part you would normally 'spot' was floating invisibly in the air, and you would only see the red part from the trap after you walk under it.