Did you modify the language resorces in the "resources" folder (using reshacker or similar tool, the files are in the subfolders and are called DIALOG.res, MENU.res and STRINGTABLE.res for each) after using extract_language.cmd? As stated in the readme, this cannot be automated. Some of the steps involved are opening the .res files, changing the language ID (sorry can't help with italian, i only know the codes for german, which is 1031, and english, 1033) and editing the resources themselves. You have to pretty much figure out yourself though.