Support System.IO APIs for SkyDrive's Smart Files
Filed on behalf of our customers.
As described in this blog post , SkyDrive has a notion of smart files  which aren't directly accessible using the regular System.IO APIs, such as File.Open. We provided sample code  that shows how one can write code that handle smart files correctly.
But to quote our customer:
It would be helpful for Microsoft to provide a full blown solution to this which maps all key methods in System.IO such as File.Copy, File.Move etc. to their WinRT API equivalents. This issue is starting to crop up on support forums as it has caught many developers off guard.