I\'ve got a UICollectionView, which works ok, until I start scrolling.
Here some pics first:
I had a similar problem with paging. Even though the cell insets were all 0 and the cell was exactly the same size in width and height as the UICollectionView, the paging wasn't proper.
What I noticed sounds like a bug in this version (UICollectionView, iOS 6): I could see that if I worked with a UICollectionView with width = 310px or above, and a height = 538px, I was in trouble. However, if I decreased the width to, say, 300px (same height) I got things working perfectly!
For some future reference, I hope it helps!