PC Application: Download to your computer and then unpack its content. Then you can run the application. Ignore security warnings, if any, the application is safe.
Mac Application: Download the app file to your computer, extract its content and add .app to the folder name then you can start the application. The tool is known to be compatible with OSX 10.14 Mojave.
IA Temperaments Pack
IA Temperaments Pack - containing 50 different organ microtunings in Hauptwerk 3 format including 4 temperaments from J.S. Bach, 8 Werckmeister temperament variants and more. Each pack contains 25 historical microtunings.