ACA2007 Light is only a simple and fast error scanner for your aircraft.cfg files like the error scanner that is present in the MRAI Setup wizard. Read more
ACA2005 is a program which scans the [fltsim] sections of the aircraft.cfg files for all kind of errors and gives you the possibility to edit these sections. Also there is a possibility to create a timetable of the flights to and from an airport and to list the installed flightplans. See the documentation for more details. This is version 1.5 which does handles more then 200 FLTSIM sections.
AITA2004 is a program to monitor your AI traffic in air and on the ground and log the selected events and time to a (comma delimited) log file. See the documentation for more details.