This is just leftover code that needs to be updated...
this:
<?php if (!(strcmp(($rsRecordSet->getColumnVal("CategoryID")), WA_AB_returnPreSelectValue($WA_PreSelect_RelationalTable_1, ($rsRecordSet->getColumnVal("CategoryID")))))) {echo "selected=\"selected\"";} ?> >
should now be:
<?php echo(in_array($rsRecordSet->getColumnVal('CategoryID'),$RelationalQuery_1->getSelected())?"selected":""); ?>