I thought this issue sounded familiar - I really need to check my old posts, etc (see
https://lists.ovirt.org/archives/list/users@ovirt.org/thread/VBCK7C3Z22K7...).
To document the "solution" I'm posting this here.
In short the solution (for me) was to accept the default names for the Data Center and the
Cluster and then edit the names to what was required/desired once the engine was
successfully deployed. This thread
(
https://lists.ovirt.org/archives/list/users@ovirt.org/thread/IDLGSBQFX35E...)
gave me the clue.
Cheers
Dulux-Oz