Yes, the forum has disappeared, but official support for the phpld script has been discontinued long ago. The owner there had threatened to get rid of the forum years ago and once told me in a PM that the people who had just bought a script were not worth the time and effort. I also get a lot of complaints in my own forum from users who bought the script, stating that their support requests for errors were constantly unanswered.
I've had a third-party support and development service for the phpLD script for years, based on my own forum, and as far as I know, the only mod developer still working. In my forum, which leads nowhere, you will also find free information on common and aborted code errors that refer to phpLD. I am not sure if I can publish my forum link. So just search for Google / Bing for my username!