@yifanlu: Just a minor question: I'm building installers/uninstallers for the localization. Everything works, except for one minor thing: I can't figure out how to set the update progressbar to 100%. I checked your usbnetwork code, and I see you're using a function called update_progressbar in your code.
But where on earth is this defined? I can't find it anywhere, neither in your code, nor on the device. I tried src'in the functions as you do in my scripts, then calling update_progressbar 100, but it just won't do anything.
So, what kind of Voodoo magic did you use?