I tried using another computer and it worked just fine. More searching online revealed that this was a Windows related error and nothing to do with macro express. I resolved it using the info from this site https://www.winhelponline.com/blog/error-there-is-no-script-engine-for-file-extension-when-running-js-files/
I can't say exactly what registry edits at are being made to Windows when you run this, as I'm not that knowledgable in this area, but I ran the attached file and things are working fine now.
jscript_fix.zip