Easy way to install the ffp plugin suite on your Zyxel NSA server. FFP will give ssh access , you can use it to install many useful packages.
More about ffp you can find here: http://zyxel.nas-central.org/wiki/FFP-stick#FFP
2. Disconnect the internet connection on your router but leave the lan working.
3. Copy both files on your nas admin\zy-pkgs\
4. Open the web interface of your NAS and login as admin
5. Go to Firmware and packages – Packages – press retrieve list from the internet.
6. Find FFP in the list ,select it and install it.
7. Open putty and ssh to your server. You can login with root / your admin password.
8. Run uwsiteloader.sh for the repositories, there are several . For more info read on your-nas-ip/pkg/ffp/