Just extract the file and copy the folders to ~/.icons. Subdirectories are not detected so you need to make sure that the icon folders are the first subdirectory in ~/.icons:~/.icons/gnome-braveand not:~/.icons/gnome-colors/gnome-braveThe new icons will show up in the settings where you can select them, no need to install.
When I choose icons for my desktop-files, I have the issue that a lot of them will not load in Tint2, especially the action-icons. What could cause this? Furthermore, when I look in /usr/share/icons there are a couple of Faenza-Crunchbang folders, but there seems to be very little inside the folders. Can I get these icons anywhere else?