its likely because you are using cpanel to do this and its being a stickler for permissions and quota's, have you made sure the account you are running it under has a large enough quota > approx 175GB?

also have you made sure you have amended the scripts so that it downloads into appropriate paths?

for anonymous ftp on cpanel, you have to have files in the public_ftp folder and have anonymous ftp enabled within whm, however public_ftp wont serve out on http, so you will probably need to symlink your public_html folder to public_ftp for that to work or duplicate the whole mirror which would be a waste of resources and hd space

i cant say i would recommend mirroring from a cpanel server but its not impossible