Inkscape uses the Nullsoft Scriptable Install System (NSIS) for its Win32 installer. The package can be found here [].
A lot of work has been contributed to the NSIS files, which are found in /packaging/win32. The files have been set up to work from a typical Inkscape project directory, such that /packaging is at the top level, and the Inkscape distribution directory is also a top level directory named /inkscape. inkscape.nsi is the main project file, and the .nsh files are the language strings provided by our kind translators.
To use, just start the "MakeNSISW" program (or start it from the NSIS GUI) and load the inkscape.nsi file. It should find all of the .nsh include files, and start processing the script. If all goes well, a file with the name pattern Inkscape-$VERSION-1.win32.exe should be created. If not, look at the output console window to see what happened.
The project file has been set up to use 7-zip compression on the output file. Try running the installer before uploading. Have fun.
Since NSIS is very easy to run, this is all of the documentation that you really need for executing it. However, we should use this page for documenting the details of the inkscape.nsi file, which is far more complicated.
Interest has been shown in using an alternate installer that produces Microsoft-compatible .msi files. Any research into such an installer would be welcome.