I was there at 6 am, first in line and all my papers in the exact order the requirement list puts them. Make sure you have them stacked in a way that you can easily maneuver with them, you have to reorganize them inside.
The first Embassy official was extremely helpful, funny and a total delight. She asked me a few questions about myself, my life and my relationship while she reorganized the documentation.
The CO was also very helpful, asked clear questions, was very polite and patient. I was missing a document that I hadn't known how to procure and she explained to me very clearly how to go about it.