Winpwn 2.5 error

I tried winpwn 2.5 beta 2 to activate and unlock my iphone 2G. I upgraded it to 2.0.2 and everything seems to go well. But right at the final steps where it's said ''prepare iphone for custom ipsw'' or sth like that an error appears. That's the type of error when a window appear and tell u they have some problems, if u would like to send error report or don't send. I tried it several times but it keeps being like that. Now, I have no idea anymore.