Sorry Gergely but thats ACARS.
AFCAD is basically a program that lets you change the way AI aircraft use airports, and the way the ATC tells you to use airports.
You can't actually change the layout of airports or the way they appear in FS, but you can change the way the runways are used and you can change where taxiways are, and where aircraft park.
Recently I used AFCAD to edit EHAM because I fly there so often. I have almost all of the project AI airlines installed, but by default, almost all of the aircraft at EHAM are KLM. To get round this I edited the AFCAD adding hundreds more parking stands so that there were many more aircraft able to park at EHAM. To cope with the extra traffic I then edited the runways so that one is used for landing and one is used for take-offs.
There is a very good instruction manual included with the AFCAD program, its definately best to read through it first.
As for project AI, make sure you have downloaded the installer program, otherwise nothing will make sense.