I have done some random searching around the forums and discovered Must restart unbound and unbound-dhcp-leases-bridge to find host and running the following steps:
/etc/rc.d/init.d/unbound restart
/usr/sbin/unbound-dhcp-leases-bridge -d -vv
means that 192.168.10.137 can now be pinged across the network by name.
-Andy.