Hi, thanks for getting back to me. I made sure that sysadmin was set on the correct SQL instance we're using. Wierdly, sp2013_config was te Db in the log as reporting the login problem...
Anyway, once the DBA set up sysadmin for the service account as needed, and we restarted the installer to clear the cache, it's progressed OK.
Are you OK with leaving this ticket open for now, whilst we work on the install, to capture any other problems here and keep the history together?
Thanks for your help so far,
Cheers, Martin