The MovePhoto method moves a photograph from one photoset to another. This method can also be used to change the position of a photo within the photoset.
void MovePhoto( long srcSetId, long photoId, long destSetId, int index )
The photosets identified by the srcSetId and destSetId parameters must be owned by the currently authenticated user. In addition, both photosets must be of the same type. It is not possible to move a photo from a gallery to a collection and vice versa.
To change the position of a photo within the photoset, specify the same photoset identifier for both srcSetId and destSetId. The index parameter is zero-based, that is, the very first photo in the photoset has index 0, the following photo has index 1, and so on.