mozip is a small command line utility written by Hung-Te Lin. it is used by Mozilla Suite localizers to create localized installers for Windows, because it can add and remove packages from the install program.
in the coming weeks, i plan to build a GUI version of it, so we won't need to open a dos box in order to use it. as a first step, i compiled its source with the zlib source, with no particular problems. i don't know how to create a UI for windows using the Windows API or MFC, but i do know C#, which is quite easy. since C# can use libraries compiled in C or C++, this seems like the obvious option.