extending my cover of NIS 2011

Hi there, I recently updated from NIS 2010 to NIS 2011 online within the program. I now have about a month of coverage left with NIS 2011. I would like an actual cd-rom with NIS 2011 on, just in case of any problems,but when I get one,do I have to install it or just type the product key into the relevant box under "express renewal"?  Thanks, Seabiscuit.