UPDATE DECEMBER 2017
Hi everyone, thanks for watching our build talk and following the link to the code sample.
At this time I have even more bad news. As many of you suspected, the code for using CreateFile2 to access brokered locations was pulled from the Fall Creators Update at the last minute. There were issues with the security model that resulted in us being unable to ship it in the current form.
We have not stopped development though and are working to try and bring CreateFile2 to the universal platform without compromising the security of the operating system. We will make another announcement once there is a working prototype in the system for you to try out again.
Sorry for the delay, and thanks in advance for your patience