Thanks John. So, when I drop in in the sequence and it asks me if I want to conform the sequence to it, and I do, then it still doesn't work. BUT, when I drag the clip onto the icon to make a new sequence from it, THEN it DID work! Iw as able to export the whole thing, and no pink glitches.
So, in the short term, my problem is solved. However, I'd still like anyone's input on this, because ultimately, I need to be editing this video in a 23.976 timeline. I should be able to drop something at 31.62 fps or 2.8 fps or whatever on this timeline, let alone something at close as 24 fps. Right?