What you're trying to do can be slightly tricky... you basically have two options:
1) Download and check in the "DAT Package For Use with Mcafee AutoUpdate Architect" package from the McAfee download site. (Which is what I think you're doing at the moment.) This option is manual, unfortunately. Or:
2) Download the entire contents of the McAfee commonupdater site, and copy the entire structure across to the share that you're using as a UNC source repository. You will then be able to schedule a pull task from there.