How much does it cost to download an additional state to desktop Deluxe after using the one that was included? This will be another family member filing fed and state taxes on desktop Deluxe.

Your CD/download included the software for one specific state program of your choosing.   If you need to file a return for another different state, each additional state program is $45.  

Thank you for responding.   Does the $45 state download fee cover the $25 e-file?  Or, is it a grand total of 45+25=$70.00?

No---the download fee for the additional state does not include e-filing.  There would still be a $25 fee to e-file the state return.  You can avoid that state e-file fee if you print and mail the state return.