As promised, here is what I observed during my interview experience. [Note that this is my personal experience and what others have gone through might be different in the details.]
If your appointment letter states the appointment time as 8:00 am , you'll have to arrive there at least by 7:30 am. Remember to take all your documents with you.
After going through a routine security check (Very thorough! Be advised to put all metallic objects at home or with a friend outside to make this experience as pleasant as possible), you'll be allowed to enter the waiting and interview room.
At the entrance to this room, you'll be received by a lady who will give you a folder/case with a paper containing instructions (in Amharic and English) on how to arrange your documents. Put your documents in the stated order in the folder, and return to the same lady. After the lady has checked all the documents and if everything is in order, she will call you and give you another paper (to be submitted in the afternoon, in Amharic and English) that details the terms and conditions under which you will be treated and to which you'll show your agreement by signing, along with a slip that states the interview time (1:00 pm). Note, the interview is conducted in the afternoon.In the afternoon, you will pass through the same checkpoint.
After entering the interview room, you will be called to another document checking session, and if everything is alright you will be told to pay the 330 USD at another window (clearly labeled). After paying the fee, you will take the receipt to the document checking lady. Here you will be given a choice between Amharic and English for the interview language. Every consular officer has a local person by his side. Finger prints will also be taken at this window. After this, you'll have to wait until your name is called by the consular officer. When your name is called, you will go to the window number to which you are called. Here you will be greeted by the CO, swear on the authenticity of the information by raising you right arm, will be asked a few questions, and, if everything is fine, you'll be told you qualify for the DV and be told to sign the original document you have sent the KCC. After signing the documents, your educational and work experience documents will be returned to you. The officer will also give you a yellow paper containing information about USCIS fee. [If you have not registered for DHL courier services, you will also be receiving instructions on how to do it.] That's it!
Things to note before going to the interview:
-Have a renewed kebele ID card, because you'll be required to show it at the entrance gate before going in for the main interview. (Your passport will be collected in the morning.)
-Name spelling discrepancies didn't seem to matter, not at least in my case. (I had the wrong vowel(s) in my first, middle and last names on my high school transcript.)
-Have photocopies of ALL your documents on both sides of the leaf.
-8th grade certificate was not necessary, and it was returned to me right away.
-To expedite the processing of your visa, please register for DHL courier service before going to the interview. And have your registration confirmation sheet with you.
Questions I was asked included (paraphrased):
-Have you lived outside of Ethiopia for more than a year?
-What's the highest level of education you have attained? Where? What institution? What field of study?
-Where do you work? What is the nature of your work?