Sure I don’t mind testing on my site! Just let me know what you need.
I understand what you mean by adding the 4th line, makes sense but like you said, it won’t be linked!
Just a question though, is there a reason why the “district” field would be placed above the country field between the city field?
Again taking London as an example in my own directory, we have a placed the district in between the “address line” and the “city” fields. Actually this is how most I think are written in the UK.
You can see in the example here on our website http://bit.ly/1sMY3K0 where “Mayfair” is the area or district bewteen “Address line 3” and “city”