Due to a disc format I have had to re-install "Rich Diamond". Unfortunately it requires a new release code. So far I have had no responses from Core Concepts and the last date at the bottom of the game page is 2009.
They seem to be selling new copies of Rich Diamond, but I don't want to pay for a new copy, besides being unsure it I'd really get a copy.

I assume that you tried contacting them through this page?

If you have received no response, I don't know if there's anything else that you can do.

I've e-mailed them twice with nothing yet.
I did contact them regarding a forgotten password and did get a reply on that, I used reply for my second request for a code - nothing, so far.

It looks like the links are still live, so hopefully using some of the contacts on Marian's page you can get an answer.

Ana