nodswen,
The documents are critical for the case but at the interview stage. Do not mail out these docs tomorrow. Once docs are submitted to the field office and they send you interview letter they will list some docs they want you to bring for the interview. In the event that they do not list financial docs, you will still need to bring them for the interview.
The Chicago office just checks that your Case number is current(DV Selection Letter was included) and that the I-485 was completed correctly. If the above is n order they send it to the field office who will adjudicate the case.
All the best.
They will delay it, but later Joke aside, the reason people get anxious about the interview is if there is anything that you can't provide during the interview, your application gets delayed. I think initially they don't check any particulars. The lockbox checks if you submit the forms, $1070 check, DV letter, and you are current. Later, NBC checks probably for consistency between your application and your DV forms, verifies that you are really eligible, etc.
I have a distinct feeling that they don't check any particulars until the day of the interview. My IO asked me for the DV fee receipt even though it was in the file. We were told that this application goes through many hands before it ends up on IOs desk, so at every stage there may be checks for a different list of items. I know people who did not even submit DV fee and they were told during the interview that they should send it soon, after they sent it they got their welcome letter within a week. Of course every FO and IO may not be forgiving so it is best to send everything up front not to risk unnecessary delays.
Hi Minto64 and aos13, my wife (the DV winner) just received her I539 NOA letter which I didn't get to include in the I485 package. I only had my I129 NOA letter to prove her status. Do you guys think I should submit her I539 to the lockbox just in case?