Well, I tried to get the app running in the debugger and after installing gigabytes of dev environment discovered I can't run it because I don't have the latest feature update for Windows 10 installed. The reason I don't have it installed is because it hangs at 79% and I haven't been able to figure out what the incompatibility is. I'm afraid I won't be able to help in the short term. Is there any possibility it is the Windows version is causing the issue?
Sorry to hear of your hassle. I don't think anything in the app depends on the new version, so you should be able to select an older version of the UWP runtime in the project properties.