My only commercial module so far: The Blank Panel
2) Inside the ZIP there's a folder named "Autodafe-BlankPanel". Extract it in your /Documents/Rack/plugins/ folder (MAC or PC) or /Rack/plugins (Linux). Final Path should be: Rack/plugins/Autodafe-BlankPanel
3) Run Rack, you should be able to see the modules with right-click. If something doesn't work just delete the "Autodafe-BlankPanel" folder in Rack/plugins and launch Rack again.