Maybe not in the code per se ...
I've seen this kind of problem before ... the scripts are ignoring the parameters passed via the URL. With the whole upgrading thing, you may have reset an important setting to the default, or upgraded to a version of PHP which assumes a different default for this variable then an oder version:
Examine the php.ini file of the webserver hosting the review site. Search for the line setting the register_globals variable. if it is set to off, try setting it to on and restarting the webserver. If this doesn't fix anything, it's safest to turn it back off again. Versions of PHP prior to 4.2 always made global vars out of the parameters passed via the url; From 4.2 onward, this is only done when the variable mentioned above is set to true. Good PHP programming accesses url parameters via the $_GET[ "..." ] ( and $_POST[ "..." ] ) constructs.
Hope this helps.