CODE
/System/Library/CoreServices/Installer.app/Contents/MacOS/Installer /Volumes/MYUSBDRIVE/OSInstall.mpkg
You need to change some paths inside Distribution to point to the retail DVD.
change all the paths like this
CODE
<pkg-ref id="com.apple.pkg.X11User" auth='root'>file:./X11User.pkg</pkg-ref>
to
CODE
<pkg-ref id="com.apple.pkg.X11User" auth='root'>file:/Volumes/Mac%20OS%20X%20Install%20DVD/System/Installation/Packages/X11User.pkg</pkg-ref>
You can also add some Extra.pkg but it should be located next to your OSInstall.mpkg on the USB Drive.
CODE
<pkg-ref id="com.apple.pkg.Extra" auth='root'>file:./Extra.pkg</pkg-ref>
OSInstall.mpkg with Extra:
http://is.gd/BGAf
