From the Admission's Dean Interview:
AD What is the most egregious error you ever saw on a candidate's application at Chicago?
AP For the past three years we have had a completely paperless admissions process which has allowed us to cut down from eleven 5-drawer file cabinets to just one file drawer. So it's been really great. What hasn't been so great is when people submit their applications electronically without doing a thorough final review. So, as a result, we've had a few people submit their personal statement as Word documents despite having left the “track changes” function on.
AD Oh, that's awesome.
AP Oh sure, right, it's great! I mean, seriously, do you really want me to see exactly who reviewed your personal statement and see the edits that they made? Now I realize that accidents happen and it might be tricky to turn track changes off, but I also know that I'm always very careful to make sure that I turn off the track changes function before I send a document. Applicants have to always remember that they are applying to be a member of the legal profession – a job where small details matter and can literally mean the difference between having a brilliant legal career or getting sued for malpractice. What we want to see from every applicant is that they can represent the profession well by exercising good judgment, and that means paying close attention to details.
Not sure if this makes everyone feel better or worse, but as long as you didn't leave track changes on I think you're probably ok.