Sorry, I'm about to go on vacation and don't have the source handy, so this is all from memory.
The two things that come to mind are:
-You are targeting the desktop version of CLR 4.5
-You are not including the stub of SafeHandleZeroOrMinusOneIsInvalid I included just for the Metro targetting.
The first sounds less likely because you said you specifically said that you created a blank Metro app.
So it may be the second reason. Did you add the specific Metro csproj file (EsentInterop/EsentInteropMetro.csproj) that should have been uploaded with the latest copy of the source? Also, my initial version (May 4) that I uploaded left out a couple of important
stub files. Make sure you have the May 18 version.