SFS extensions can be installed on flash drive, frugal and full installations. However, the SFS extensions support of full installations is limited: they must be installed manually and cannot be uninstalled.
To install a SFS extension, put it in the root of /mnt/home first (the partition where pup-xxx.sfs, vmlinuz and initrd.gz are). For instance, I wish to install the go-oo-3.2-sfs4.sfs (an OpenOffice extension) and my Puppy is booted from /dev/sda5. I downloaded the SFS extension and placed it in /mnt/home.
Bear in mind that SFS extensions can be put anywhere; you can place links to them in /mnt/home. This way, you sort extensions by their type or name and place them in different directories, for easier maintenance. Remember, this doesn't apply to all flash drive installations, as some flash drives are formatted to FAT16 or FAT32, which aren't Linux file systems and therefore do not support links.
Then, go to the SFS files manager.
Now, click “OK” to apply the changes and reboot.
To uninstall a SFS extension, go to the Boot Configuration panel and do the same, but this time, select it on the right list and click “Remove” instead. Then, you can delete your SFS extension from /mnt/home.
Under full installations, SFS extensions must be extracted in order to be installed. There is an automatic SFS installer, but it is always good to know the manual way of doing things. In this example, I installed centerim-4.22.9-sfs4.sfs (a CenterIM extension).