I tried the fingerprinting but didn't succeed (see my follow-up post on our previous discussion). I also add a follow-up post to our other discussion which may help others who have a similar problem.
A qustion about your answer to my 2nd question: I should file a new I-485 within 180 days of the date of the 485 denial, not 180 days of the date of the MTR denial, correct?
Thank you again for all your help.