Contact App - How to ensure reply-to actually uses the persons email address & CC/BBC fields

I have set up the Contact app. There is a check -box in the setting for "Assign 'Reply-To' header to sender's email address ". Whether is this checked or not, the person's email address that fills out the form is not used when I click reply. Any suggestions on this?

Also, I'd like to be able to use a CC and BBC field for additional people to receive site emails? There is no setting for this sadly, or space to manually add extra header entries. Is there any way to get around the lack of additional header input? Advice is most welcome, please?

Regards

Robert