Please see the PDF that comes with this product. The PDF is installed with this file: 9464_5_CarraraSkiesVolume1_5.
Install the product (9464_4_ca_CarraraSkiesVolume1_4) to your Carrara application folder. Do not target 'Presets' or another folder. If you target the Carrara application folder itself, then the installer will put the files into the correct places inside of it.
This is how to see the sky presets after you have installed the product correctly.