I believe that guide is for those who have froyo and hboot 1.00 or 1.01. As you have 0.43 you need to use the rooting guide for 0.43.0.43
http://xdaforums.com/showthread.php?t=725430
olso i try to do this guide for downgrade but the phone is not rebooting 5 times
what can i do ?