Try by inserting them as sql files... i do so... just make an sql like this
Just edit the lvl and attack power in notepad, save as blablabla.sql and than run as batch file.INSERT INTO `creature_proto` VALUES ('8888889', '255', '14', '9999999', '100', '2,5', '0', '3200', '1280', '5000', '2900', '387.6', '532.95', '0', '0', '0', '0', '0', '0', '0', '0', '0', '0', '36000', '0', '0', '0', '0', '0', '0', '0', '1', '1', '0', '0');