I don't know all the specifics but I will tell you what I do know.
She got there around 6:50 am for a 7:30 am interview time slot.
They began processing at 8:00 am.
The first booth is for biometrics fingerprints - she said a very nice American made her feel at ease and joked with her.
Each booth took about an hour of waiting.
2nd Booth - Filipino man checked all her paperwork and made sure it was in order. I think he asked some questions but not sure
exactly what.
3rd Booth - not sure if this was the CO American officer that asks the formal questions or if he was the 4th booth.
But the American CO she said looked like Superman with dark hair and she was in love with him LOL...
They asked her:
When we met
How we met
Where we met
My birthday
What did she like about me
And they ask to see pictures of us together
They did look at my 2013 tax return - I'm self employed. and the I-134 form.
The I-134 was a scanned copy I emailed her - I did sign it in blue ink and scanned it in color so it would look a bit more like an original.
Then told her she was done and she could go home and wait for her Visa!