Rob,
I highly suggest that you read up on WP8 development on Microsoft’s MSDN website. It’s a great resource and will teach you how to use Visual Studio and provides plenty of app examples. I also recommend that you play with Microsoft’s sample projects and built-in project templates first to get familiar with the development environment. In my opinion, Visual Studio is much simpler to use compared to Xcode and the Android SDK, so, you should be able to get to speed fairly quickly.
>> What is the difference between building /deploying solution and your project? Are they separate or is the Solution including the project?
Doing a “Build” compiles your code into libraries/DLLs and bundles your binaries and assets into a WP8 *.xap file. “Deploying” means installing and running your compiled app onto the WP8 device or emulator. When you click the “>” toolbar button in Visual Studio, it does a build, deploy, and starts running/debugging your app all in one shot. The “>” toolbar button is also a dropdown box which allows you to choose which physical device or device emulator to deploy to.
>> Running the Store Test Kit: Im having errors with validation of screenshots.
Microsoft expects you to take a screenshot via the WP8 emulator as shown here…
http://msdn.microsoft.com/en-us/library/windows/apps/gg442300(v=vs.105).aspx
Microsoft documents the WP8 store screenshot requirements here…
http://msdn.microsoft.com/en-us/library/windows/apps/hh846296.aspx
>> I have built to device using release but still get overlayed text/debug info - how come?
That is framerate information that only shows up when you are running your app via Visual Studio’s .NET “Managed” debugger. When you stop the debugger in Visual Studio and then run the app on your device manually (tap on it yourself), notice that debugging information no longer shows up onscreen. This is Microsoft’s default debugging behavior and it’ll do the same with all other Microsoft WP8 project templates. It’s nothing to worry about.
>> A lamens guide to including c# files - do we simply stick one in the project, include it ? IE in future will need to support Admob etc so is this possible now? Can I access native audio/video features this way?
I recommend that you learn how to do this via Microsoft’s built sample projects and templates. That’s the best way to learn C# and how to integrate 3rd party XAML controls such as ads. For example, start with learning how to add Microsoft’s ad library/control to your page, which comes with Visual Studio. This will help you learn how to work with Microsoft’s XAML UI framework as well as how to add a “Reference” to another library.
http://msdn.microsoft.com/en-us/library/advertising-mobile-windows-phone-8-adcontrol-visual-designer(v=msads.20).aspx