Freshthemes are not available directly to the users as of now. The only available themes were
- Marina theme - latest
- Mint theme
- Classic theme - oldest.
which can be customized according to your needs.
The download would contain a folder, with text files containing the code that would go under each section within Admin--> Channels --> Portals --> Customize --> Edit theme to edit the existing theme. If you want to import click Import theme to import from zip file. To learn more about importing themes, click here. After customizing, Preview and "Save and Publish" the changes.