Restarting Jigdo for Windows Users

Using jigdo to download DVD images for Debian Linux, isn't documented tremendously well for us Windows users. Specifically, continuation after some problem that caused the window to close, after downloading a couple or more Gigabytes of the disc. After looking at how the documentation told about mounting the .iso.tmp file and then feeding the path to the mount point, I realized what I needed to do.
WinRar to the rescue! WinRar is capable of opening .iso files, so I renamed the DVDNAME.iso.tmp to DVDNAME.iso and extracted the files to a directory. I probably could have just opened the file directly without the rename, but I wasn't thinking. I then tried passing the name of the newly created directory to jigdo for it to scan, but that didn't work. Hmm, what to do? Well, it takes drive names, no problem, since that's how it gets old distribution disc names to avoid downloading something you already have. So, from a commandline, I just typed 'subst y: "newly created directoryname".' After that, I just gave the "y:\ " to jigdo to scan, and avoided hours of unnecessary downloading of files I'd already downloaded.