Learn the system first on other books not relating to study. Once you've experience using the system on shorter books you can use it the same way for chapters of a textbook.
1.Per chapter you'd pick 5 to 11 trigger words depending on the number of pages, form at least one question to get started.
2. Your questions depend on your purpose. What you want from the book.
3. If it took more than an hour you're not super reading. You're spending more time reading. Superreading is too fast to read. It's spotting where you should slow down to read. Since you asked about questions I don't think you have a clear purpose which is moving you toward passive reading.
4. If you didn't intend to spend so much time on a mind map why did you?
5. Yes, you may PhotoRead the book upside down.
1b. Yes you can do it that way.
3b. Not as effective.
4b. No that's not how textbooks are used in classroom. Your focus should be similar, working in modules.
It's been repeatedly posted on the forum.
Textbooks, Don't start using the PhotoReading system on textbooks until you've worked with 4 or 5 non fiction books of about 200 to 300 pages first.
PhotoRead the entire textbook at least once. If it is a book used by the teacher for an entire year, you could PhotoRead it daily for a week at the beginning of the year.
When activating, Activate the instructed sections, you can PhotoRead the section again. If you decide to PhotoRead the section again, include a couple of chapters before and after that section.
If you are having difficulty activating a chapter in a textbook. Try PhotoReading just before activating. Find other text on the subject and PhotoRead as many as you can. Activate a little from each textbook or book on the subject that you feel inclined to. Then return to the textbook with the subject that was troubling you. Often this process will help make the subject easier to understand.
Alex