If you have a .gpz file, to install, double click on the .gpz file and the preset files will automatically be installed to your preset collection. A prompt will show:  "Installed ## new presets."  Then, click on "Ok". The next time you start your host application, the Sapphire presets should show up in your preset collection.

Other ways of installing presets would be to right click on the .gpz file:

• Select “Open with” > select “Preset Browser” > click “Ok”
  OR
• Select “Open with” > select “Other…” > select “preset_browser.exe” > click “Ok”