Locked out after installing Domain / Samba

[gob]

Hi
I have just set up my first Zentyal server. All was going really well until I hit this snag.
I first set up a static IP on the server and proceeded to configure a domain, samba, mail & webmail.
This all worked perfectly until I logged our of both the web portal and server console.
I then found that I could no longer log in with my local users account (non domain account). I have also tried to log in to the web gui and console with a domain admin account but still get nowhere.

I assume that the domain/kerberos authentication has taken over the local authentication model?
I have also realised that I did not point the DNS of the NIC to look at it's own dns server so it cannot see the dns domain that the server is publishing. Could this be why I cannot log in anymore?

I have tried to access single user mode to try and change this but I cannot see a grub loader during startup. that could be down to me using a virtual environment (Proxmox) and the console perhaps does not appear until after the bood options.

Any suggestions?

thanks
Gordon