It's possible to download files and folders individually in the RushFiles sync and share solution.

If the user wants to have offline access to a few files or folders, the user can at any folder or file right click and by accessing the action menu force "Download Folder/file" or "start/stop synchronization"

Download folder/file:

Download folder/file is downloading all files in a folder/ or a single file

This is making the files available in offline usage. 

Start/Stop Synchronization:

Start/Stop Synchronization is also downloading your files, but also if you or another user add folders/files to the folder, will the system automatically download the files to be stored locally for offline usage. 

*Start/Stop Synchronization can also be enabled on a share, this will keep all folders/files available for offline usage.