Ok alarm all sorted, Sixwheeledbeast was right, the tampers needed resetting on the wireless devices. The only thing I was doing wrong was being too impatient with them, they take ages to initialize with the control panel. I left it for an hour it then allowed me to arm and disarm which cleared all errors.
Rip off merchants ADT no longer have me over a barrel...
Also, pretty shoddy information from user 'Al-Yeti'. He sounded just like the other rip off alarm fitters I spoke to today, making out it was a massive job, desperate to charge for a tiny bit of information. If you don't want to share information, why are you posting on a public forum?