I just discovered that the author of the JOTD (JST) HD installer tool for games has recently pulled his source code out of mothballs, and is once again actively updating and maintaining it. The latest version has numerous improvements, and now works under Kickstart 1.3 and on CDTV.
He's hosting it on GitHub, and you can download the latest binary from there. To get it just click on the green "Code" button, and then from the pop-up menu select "Download ZIP". You will find the jst binary in the bin directory. Just copy it C:, and you're ready to go.