Hi Jim
Normally the driver should install itself. Try unplugging the USB cable and plug it back in to see if that forces it. Also close down the software and start up again
If not go to your box in devices and printers, right click on it then click Properties, then Hardware tab, then Properties then Change Setting, then Driver, then Update Driver, then Browse My Computer for Driver Software then Browse to C:\Airnav Systenms\Airnav Radarbox\Drivers and the Drivers should be in there.
That is assuming you installed to C:\Airnav and not into the Program files location as you are advised not to install in there
Alan