Do you have the Mastering the Twister DVD? That really helped me in terms of seeing all the transitions come to life (the book is awesome, but for me at least I need to see it, and then compliment with the notes). Of course, it does take practice and you do need to drill it first to get the motion, and then second with a resisting partner so you can feel the different roadblocks/speed bumps. Try to spend time not only working the twister roll from SC but also when opponent is on all fours (the Muffle and Dodge really helped me with getting the Twister roll, the half guard roll I don't do that much but even then I felt improvement after watching the dvd several times).
Don't give up, keep working on adding whatever 10pjj you can along with the standard BJJ basics!