Okay so here is a thing. rather than roll my own input solutions etc per-platform I decided I would at least have a go at pulling the mg source from github and seeing if i could fix it. I'm not great with other peoples code so bare with but I've ran into something a little odd.
I am targetting wp8.1 and stepping through my errors in Guide.cs I notice the constant WINDOWS_PHONE is NOT defined. I figured there must be a WINDOWS_PHONE81 const or something but there appears not to be. Further more in the constructor for Guide the code block for:
#if WINDOWS_STOREAPP || WINDOWS_UAP
executes. The initialization error then gets thrown by the line:
var licenseInformation = CurrentApp.LicenseInformation;
which is not overly surprising as this is neither a windows store (i assume that means desktop app store) nor UAP application. Am I missing something fundamental or are these platform constants a little awry?