This issue has been in ZC for many many versions, but I finally got round to fixing it for my 1.5.5 setup!

In the UK, county names are not required and they have changed over time, so they cause a lot of problems. So I switch them off.

This is fine, but ZC then displays a blank line in every address it displays.

The fix is in the address format. I copied address format 6 in the database to create a new one (format 8). I amended it to be
Code:
$firstname $lastname$cr$streets$cr$city $state$cr$postcode$cr$country
instead of
Code:
$firstname $lastname$cr$streets$cr$city$cr$state$cr$postcode$cr$country
Then changed the United Kingdom entry in Countries to use Address format 8 instead of 6.

This fixed the problem, and if I ever want to use Counties again, I can switch back to address format 6