Ogone payment installation - error

Hi there, I tried to install the Ogone Modul according to instructions but got this message in the ogone-admin settings:

Fatal error: Call to a member function RecordCount() on a non-object in /is/htdocs/wp10731754_5YGPEGQC0D /www/admin/mo_ogone__setup.php on line 186

/**
   * Install new tables, update fields and clear cache
   */
                protected function mo_ogone__install_payment_log_table ( )
                {
                               include('../config.inc.php'); // get $this->dbName from config.inc.php
                               $sQuery = "SHOW TABLES FROM ".$this->dbName." LIKE '%mo_ogone__payment_logs%'";
                               $oResult = oxDb::getDb()->Execute($sQuery);
                               if($oResult->RecordCount() == 0) // table doesn't exists (LINE 186)
                               {
                                               if( $this->getConfig()->isUtf() )
                                                               $sCharset = ' ENGINE=MyISAM DEFAULT CHARSET=utf8';
                                               else
                                                               $sCharSet = ' TYPE=MyISAM';
                                               // install sql-table mo_ogone__payment_logs
                                               $sQuery = mo_ogone__main::getInstance()->getOgoneConfig()->logTableCreateSql . $sCharset;
      $this->mo_ogone__execute_sql($sQuery);
                               }
     $this->mo_ogone__addOgoneStatusColumnInOrderTable();
                }

Used the latest Ogone version for 4.5.4 CE (Azure) from the OXID-eXchange area. I think it has to be a database problem, can somebody help me with this, thank you.