For most authors using CreateSpace, the transition to Kindle Direct Publishing (KDP) is smooth.
A simple three-step process helps you make the transition. Your books remain available for sale at Amazon and other distribution channels. Your royalties remain the same (except for royalties in Europe for books under 100 pages). The books are printed in the same facilities used by CreateSpace. The guidelines for interior and cover formatting are nearly identical.
It should be a seamless transition, and for most authors it is.
But when millions of CreateSpace books move to KDP in a short time span, a few unfortunate authors are bound to experience one or more issues.