UPDATE.
I have spoken with Texecom support (Whom were excellent) and with their assistance have returned the panel factory defaut settings.
Zone 8 now works perfectly so it had to have been me whom disabled it, (As suggested) I can only think Isomehow managed it by accident. (Fat fingers)
In any case, to those that replied, thank you, your help has been very much appreciated.
Regards, Dave Walton.