When I turned on my IX2-200 after a few months of rest, it appeared to be dead. So I had to guess some details, and couldn't fully test my script.
Anyway, the script can be found here
Create a dedicated share, the name doesn't really matter. No spaces, but I don't think spaces are allowed at all. Extract the script ffp-starter.sh from the zipfile, and put it in the share.
Login over ssh, and execute the script as root with the 'install' argument:
The share can probably be found in /mnt/pools/A/A0/<sharename>/. If you can't find it, try
grep -A 10 -i "\[<sharename>\]" /etc/samba/smb.conf
The script will download fun_plug.tgz to the share, extract it, patch /etc/rc.local to start ffp on boot, and add a stopscript to /etc/rc6.d/, to cleanly stop ffp on shutdown.
On start of ffp the default shell of root and admin are changed to /ffp/bin/sh.
If you want to remove ffp, do not just delete the share, but run 'ffp-starter.sh uninstall'. This will remove the patch in rc.local, remove the stop script.
Logfiles can be found in \\<NAS>\<ffpshare>\var\log\