Huh? I think you're pretty confused. Solex is an application on your phone/tablet. It has no bearing on what the controller does or displays. There is no such thing as Solex 3.0. Open Solo firmware on your copter and controller is 3.0.0 if you did that upgrade.
If your controller is showing 999 or some other crazy high altitude, it means you didn't install the controller update package for ArduCopter 3.6 and 3.7 compatibility as detailed in the instructions. OpenSolo/documentation