Yes resetroot.bat is wrong.
I downloaded and installed XAMPP today (1.6.6a) and after i changed root password i was no more able to use phpmyadmin (even when i updated config.inc.php).
So i wanted to reset root password with that batch file but it is not working.
I had to reinstall XAMPP and then i checked it and corrected resetroot.bat (it had wrong number of columns). I had to increase number of 'Y' entries for root to 28 (instead of 21) and also added one zero at the end. (for pma user also - adding 7 'N' and one zero)
Now at least i can reset root and pma passwords (but still can't set it to different then empty for some reason...)