HZGaming you set the test mode on in Construct 2 Windows 8 plugin and then export and in visual studio you create a test certificate and then run it with Visual Studio debugger. You should create some action for the is expired command in C2. Maybe one tap on some object makes a sound if the licence has expired. Don't forget to export it again without the test mode on in C2.
I'm struggling myself with the Windows phone universal app export trial.