My guess is that if it's a sign-up from a referral site, perhaps the action tag is different. But it is just a guess, only the OP can confirm. If not, then mystery solved - the forum sends all data as POST, and there isn't a form field called "ref" anywhere in the form.
Another weird thing with
$rrr is that sometimes it's an array as the result of
mysql_fetch_array(), and sometimes it's a variable as in
$rrr = 0, but in the check it's always assumed to be an array.
I know it must be frustrating that no-one is just doing that, but using these obsolete libraries to access your database is something that most have gone away from, and probably don't really remember without spending time looking them up. There would then be the issue that a forum contributor appears to be advising you to carry on using old code, even though it has security implications. For any general site that is an issue, but for a betting site which presumably has some financial dealings with customers, that's a serious mistake.
And finally, you've paid someone for a product which should work, why can't they answer the questions you have? That's what the money was for.