Download the package from the resource page and extract all files into one folder (keep all three files together). Right-click HONDA EDITOR-V1.39_Loader → Run as administrator. This is the entry point — do not launch the main exe directly. Once the interface opens, use Open to load a supported Honda ECU bin file, select the correct ECU group (Keihin 1MB / 2MB / 2.5MB / 3MB), and you're ready to work.