I run on the exact same problem, and had it sorted the exact same way. Is there a new beta somewhere with whatever the typo is fixed?
I also have this problem when trying to install symfony in PEAR where I get a permission denied error to rename a file in the xampp php folder, rather than the php/pear folder, but it seems that's what the installation is supposed to do. Have you come across this problem? Could it be that the problem with the renaming has something to do with the security settings?