Welcome to the Router Forums. The upgrade control board will allow you to use Mach3 to control your little CNC. There is plenty of documentation for Mach3 and a lot of people using it for their machines. In my opinion that is a good choice to get away from the GBRL control.
Mike Your BRAIN Is The Most Important Power Tool In Your Shop. Turn It On Before You Turn On Any Other Power Tool. A Disability Is Only A Disability If You Let It Be One