When I watched the opening for 0.2 and I saw the Castle and I didn't think it was the Castle of Dreams. To me it looks like a completely different castle. At first I thought it was the Enchanted Dominion but looking at it again I can see that it is surrounded by water which both worlds are not and this castle has a different structure and build to it then the Castle of Dreams. I've noticed that the Castle of Dreams has a pointy clock tower but this one doesn't show a close or a pointy tower.
I've attached pictures comparing the two versions of the Castle of Dreams from the ending of Birth By Sleep and how it is seen in 0.2 Birth By Sleep and the castle that we see in the 0.2 opening.
If you can convince me that this is in fact the Castle of Dreams I would love to hear why, because to me they look different. Also if you believe that it is not too, then what world could it be? Possibly a new one?