yes you are supposed to explain things as much as you can, and yes it is important to explain feelings and even if you feel as if you can smell something from the image then say that too. When you explain aloud to a listener or whatever you talk to, you have to say things in a way so that it can be understood by that other person, in the process you open your own mind to what is going on and it makes the image more clear.
Also if you choose you need to stop and see where the image goes you can but it is recommended that if you do that try to explain the main theme of what you see ex. "I am now at an ice cream shop" as opposed to "i am at an ice cream shop sitting approx. 2.4 meters away from the table next to me which is blue and blah blah blah..."
and to your third question yes these images are as if they are being seen by your minds eye, not your eyes so describe the ones coming into your head (by the way it took me a while to figure that out too)
