Missing Roles in Drop-Downs for Add New Users

ClvrTv Inactive
El Presidente
Friendly Neighbour

This is a little strange and I hope it's not a silly mistake or lack of understanding on my part. I have created a bunch of blogs using the same single master admin account / email.

I'm now trying to add additional users with various author / editor roles to certain blogs (subdomains). In the core admin "Add New" under Users section the drop-down for Role is blank. I can create the user, generate the email, validate with the link and get a password. But when I try to use the new account to log in it says I don't have any permissions for that site.

I thought maybe there was a bug or something some where and maybe Add New Users plugin would circumvent. But it has the same issue - on sub-blogs the Role drop-downs are blank. On the main blog, they have the expected values.

What am I doing wrong? Currently, I can't add any users above the default subscriber level on any of my blogs. Arg!

Many thanks!