No, it is not normal for the bottom ring to stop moving. However, I think I can say without giving anything away that you have nothing to worry about. You should still be able to progress. Good Luck!!
"Punctuality is for people with nothing better to do."
go somewhere very quiet and listen. as for the number of ball bearings, just try different ways of listening to the isis. I do not think there is any real way to tell until you open it up. Sorry if this is vauge and unhelpful.
"Punctuality is for people with nothing better to do."
Don't forget to take a picture of your open ISIS with your username written on a piece of paper. PM the image to Gatekeeper and you will be granted access to the ISIS 5% club.