Muhammad Farrukh, on 04 March 2012 - 17:45, said:
Well, I ran Add-AppxDevPackage.bat, command port promted me to Press any key to continue, and then nothing happened.

I know I did something wrong

I'm not around my Windows 8 system at the moment, but looking at the actual .bat, it looks like you have to run it from PowerShell.
REM #######################################################################
REM # Add-AppxDevPackage.bat
REM #
REM # <summary>
REM # Add-AppxDevPackage.bat is a PowerShell script designed to install
REM # Appx developer packages created by Visual Studio. The Visual
REM # Studio "Prepare Package" creates a signed Appx to a local target
REM # folder. The target folder will contain the .appx application file,
REM # the signing certificate .cer file, the Add-AppxDevPackage.bat
REM # script, plus a .\Dependencies\ folder containing all the
REM # framework packages used by the application.
REM #
REM # When executed from a local directory, the Add-AppxDevPackage script
REM # simplifies installing a VS developer package on a new computer by
REM # automating the following functions.
REM #
REM # 1. Installs all the framework packages contained in
REM # .\Dependencies
REM #
REM # 2. Installs the signing certificate .cer file into the
REM # local machine Trusted Root Certification Authorities store.
REM #
REM # 3. Installs the application package .appx file.
REM #
REM #######################################################################