When I watched the animated exercises online, I noticed that the Pelvic Tilt was described somewhat differently than in the SWSY book. Is there a reason for that? Is it not good for the back to go as high as the book seems to suggest?

It is fine to lift higher. The animation for Pelvic Tilt shows the beginner level. Just be sure TILT the front of your hip bones towards your shoulders. Think about pressing your navel into the floor as you use your stomach muscles to do the work to TILT. You should feel the effort in your stomach. Be sure that you are not using your thighs or legs to lift your buttocks. Your legs should feel light.