Hi,
My advice is to keep the website live until the whole thing is resolved.
Persimmon threatened me with legal action and also threatened the company hosting my site with legal action. Both the web host and me told Persimmon to put up or shut up. The fact is that as long as you are factual and keep the website updated regularly they cannot do anything.
www.Pishsimmon.com 7,000 hits and rising!
The other important part is that if you have a forum or guest book the housebuilder can post comments on your site - meaning the site is no longer one sided and therefore even less of a legal worry.
I would also recommend when you meet the MD that you have a witness with you. I am sure he will not be alone. Ever noticed the site managers always arrive in pairs to back each others stories up?
Good luck with the meeting!