1) Would it be possible for fields that are set mandatory to be only applicable for front-end users? Meaning, when we as back-end administrators update a user record, the fields from the back-end are not mandatory so we do not need to complete it before saving and closing the record.
You can turn off validation for backend within CB > Configuration > User Profile by setting "Fields Validation in User Management" to "No".
2) In the sender display name for the Profile Logger notifications, there is this "Sign Up" appended to the name of the site. How do I get rid or change the "Sign Up"? I'd assume that it should be using Language Override plugin and the en-gb language to change a line of the script. But I am not quite sure which line to change.
Language override plugin isn't necessary anymore as language overrides are now built into CB. See the below regarding how to use them.
www.joomlapolis.com/blog/kyle/18701-language-overrides-have-arrived
This shouldn't be specific to CB Profile Update Logger though as core notifications send the email subject as the following language string.
Code:
'EMAIL_NOTE_SITENAME_SUBJECT' => '[sitename] - [subject]',
Most likely your sitename within Joomla global configuration contains Sign Up. You can override that string to be just [subject] though or whatever you like.