5.18.4 Windows installer
All installation messages of the windows installer are kept inside on single file, which also acts as template for any new languages to be added:
The NSIS installer does not support Unicode yet, it assumes no encoding and just copies the bytes as is. Therefore the encoding used is mentioned in the comment section in the header of the .nsh language file. In order to display the messages correctly, the default language for non-Unicode applications in the language control panel of your Windows installation has to be set appropriately.