The one by SaTa (called scconv, you should be able to track it down by searching for that name) just appends the 512Byte header that is needed to run homebrew on a Supercard to whatever file you drop onto it. If the file already has a header, scconv.exe just blindly adds a second one which I'm pretty sure would give you white screens when you tried to load it, though I've actually never tried loading a file with two headers.
This "magic" one actually looks at the file first and if it already has a header, but not the right one (there's a few different loader headers out there for different hardware), removes it and appends the proper header for Supercards. It even checks to see if there's multiple headers appended and removes all of them. Also, apparently some homebrews don't even need a header, this program checks to see if that's the case with the file you dropped on it and if so, doesn't apend any header at all. That's the "magic," I guess. It's a pretty good program.
I don't know about this Moonshell Patcher thing, anyone know what it does or where I can get it? Is it only for the Supercard Lite or does it work with normal Supercards, too?
...word is bondage...