Can I restore an Elan system?

I purchased a house wired for sound and video. There is cat5 and component cabling. Part of the head unit was taken out by the previous owner. What's left is an Elan HD series multiswitch with panels in 9 rooms. 4 of these rooms have touch screens. There are sonance amps that power speakers in all the rooms. There is also a marantz tuner that works and can be turned on from all of the rooms as well. The whole thing sounds nice. The issue is that with some of the 'brains' of the unit removed like an audio-request and maybe other components I am unable to connect peripherals to the system. I'd like to try to enable the sound system for compatibility with itunes and still keep the ability to turn on 9 different zones.

I've been hard pressed to find an Elan dealer willing to support this system and have gotten suggestions to remove the elan components and use sonos units or savant. Any suggestions for something more budget conscious that can utilize what I already have in place?

Thanks.

Any thoughts? There is an S86 multiroomswitch and a Marantz tuner. How do I connect an audio server compatible with itunes?