Harmonizing script_command return value

--Fix bugreport:8249 (instance_announce)
Script command need to return SCRIPT_CMD_SUCCESS (0) otherwise they
display a ShowDebug.
Stating to harmonize return value for script_command to prevent issue
hapening again.
--Fix flood message "Transforming into monster"

src/map/clif.c

@@ -9687,7 +9687,7 @@ void clif_parse_LoadEndAck(int fd,struct map_session_data *sd)
 	if (sd->sc.opt2) //Client loses these on warp.
 		clif_changeoption(&sd->bl);
 
-	if (battle_config.mon_trans_disable_in_gvg && map_flag_gvg2(sd->bl.m)) {
+	if (sd->sc.data[SC_MONSTER_TRANSFORM] && battle_config.mon_trans_disable_in_gvg && map_flag_gvg2(sd->bl.m)) {
 		status_change_end(&sd->bl, SC_MONSTER_TRANSFORM, INVALID_TIMER);
 		clif_displaymessage(sd->fd, msg_txt(sd,1500)); // Transforming into monster is not allowed in Guild Wars.
 	}