You should instead make a list, parking by parking, of what you believe are errors so, we can check, parking by parking, if they really are errors (and fix them in the official AFCAD, of course), or simply limitations of the AFCAD system in FSX.
For example, changing the parking radius would affect the type of AI that will be allowed to park on a certain spot, but it will also affect jetways, setting it too small might reject airplanes that were supposed to go there so they will be forced elsewhere, possibly even in remote areas, if there aren't any other spaces large enough, but setting it to the correct size, would have the jetway from the nearby parking moving instead of the correct one so, in this case, it's nothing that can be fixed, because there will be a problem one way or the other.
That was just an example, to indicate that something that might look like an "error" of the AFCAD, has been made intentionally, with sound reasons.
But please, make a list of the things you believe should be changed, and we'll have a look at it.