Disable login features

Hello,
I don’t need to use login features of cimy user extra fields, I just use this plugin to add custom fields. How can I disable login? It’s conflicting with another plugin (Profile Builder Pro)

When I login with invalid credentials I get which is not what i expect. Is this a function of cimy extra user fields?

http://www.theteachertutors.com/tutor-login/?login=failed&wp-error=%3Cstrong%3EERROR%3C%2Fstrong%3E%3A+The+username+field+is+empty.

Please assist.
Thanks!

http://wordpress.org/plugins/cimy-user-extra-fields/