Like the others have said a lot of it is finding your style. I personally read relatively quickly and remember small facts about article well.
I liked the mapping idea until they came out with the highlight feature which has some quirks. I personally like to speed read the article, which for me entails skimming quickly through the article so I can have an idea for the tonal questions and get the layout to help me find the general area I need for answers. I also take this time to highlight buzz words, these include things like percentages, years, names, and words like however and but. I then flip to the first question. If I can answer it great if not I start going through the passage a little slower and once I find the answer I select and move on. I rinse and repeat.
This strategy has gotten me good score on the BC RC and also keeps my speed up so I don't have to worry too much about rushing the last paragraph.
The only other thing I can say is read science articles everyday and try and mix up what you are reading (i.e. microscopes, bacteria, plants, dinosaurs....) Talking with others this seemed to help make reading about strange topics a little easier come DAT time. Hope this helped.