Lan Game Question - Patching

I saw that a single serial key can be used to play a lan game between two computers. (https://forums.sinsofasolarempire.com/162389). I purchased the game and would like to try a lan game with my wife. I installed and registered the game on my laptop. I  assume version 1.14 is incompatible with the basic install version. How do I go about patching the game on my wife's non-registered computer? Do I just use the same serial key on her computer and hope doing so does not invalidate my laptop's version? Can a serial key be used on more than one system?

Thanks in advance.