network storage server + time machine?

I just got a Central axis network storage server. I have it set up as a networked hard drive with media server enabled.

now I can move stuff in and out of it with no issues but what I want to know is how can I make time machine use it as my back up drive?

I found a program called itime macnine that enables what I what need to do but I get a time machine error:

The backup disk image could not created