The instructions that I have given you are perfectly fine.
Follow them exactly, and it'll be OK.
Anything it tells you to do, do it.
If it doesn't say to do it, then don't.
I've followed the same instructions before to revert from v11 to v10, and it worked fine.
You will not need to reburn music or anything else, all the music or video files that worked with v11 will work with v10 as well.