ReadyNAS 212 Apps - Asterisk

I am trying to configure an Asterisk server running on my ReadyNAS 212. I have it loaded and it's running Version 10.0  Looking at where the code base is now its running at version 18.  How can I upgrade the software? Can I upgrade it?  or does someone have to compile a more up to date app? Do you know how to access the  configuration files? Has anyone had sucess doing this? Does anyone know how to configure FXS ports with a Grandstream HT818? Thanks in advance!