Carlos, That's a lot of questions, but I'll do my best here to help get you on your confident way! Photos or life, either is fine. Life is harder, but probably better for you if you're up to the challenge of "binocular vision" and distractions and a changing environment. Photos are easier because they stay fixed and are already flat, so starting with photos is good for any student who finds this scary. Working from other artists is fine too, but the problem is that artists take liberties, and you may find that their views don't quite conform to the world the way romance stories don't quite conform to romance. If you want to work from the examples in the video, why not? They were from students working to "tell the truth" of their rooms, and may get you started with their simple approaches. The increase in speed is to start you slowly enough not to freak out, but when you are comfortable, speeding it up to increase your focus on what's important: eye level. I think it's even a good idea to say out loud the "up goes down" and "down goes up" mantras because that is the purpose of this lesson — to drive in that awareness. Remember, this is not about slick drawing, it's about noticing, now and forever, what's above and below you, and drawing it with ease. Norling's books are good. Use them. Use any books that help. They may add things I have not taught you. But the job here is to draw room after room after room, learning to aim up, down, and away.