First, the LFS (Lua File System) library is not supported on WP8. This is a 3rd party library (not written by Corona Labs) which does not compile on this platform. So, you cannot *require* this library into your app.
We document what Lua APIs and features are supported on WP8 here…
http://docs.coronalabs.com/daily/coronacards/wp8/support.html
I recommend that you first following our WP8 “Getting Started” guide here…
http://docs.coronalabs.com/daily/coronacards/wp8/index.html#getting-started
This will show you how to create a WP8 Corona app project, build it, and deploy it to a device or emulator. Once you are comfortable with this, I recommend that you have a looking at our porting guide here…
http://docs.coronalabs.com/daily/coronacards/wp8/portapp.html
I hope this helps!