Always ensure your sigpatches are up to date to avoid "clogged" or "could not start" errors.
Right-click Part 1 and select "Extract Here" using 7-Zip or WinRAR. It will automatically pull data from the other parts. SAMWAR5-(USA)-NSwTcH-[BASE]-NSP-Ziperto.part1.rar
If you'd like to find the or need help with extraction errors , let me know! Always ensure your sigpatches are up to date