johnor999, the original request was for "a GUI for lights positioning and rendering/preview".
Creating an array .def, a text file, is a straightforward task. Once you specify the reference position, you simply write down the type of light and its position relative to the reference point for each element. Since such arrays are, generally, oriented straight lines of light, most of the work is copy and paste with a subsequent adjustment to the Y value. If you columnize the data (as in the samples), most errors will be readily apparent. Compare this with the (much greater) effort and precision required to position each element graphically.
Regarding "verify and test", since AFLT is "unaware" of the environment in which the array is to be used, all such a GUI could display is the lateral position of each element relative to the reference point. (In order to show the configuration of lights within an element, it would be necessary to analyse the .mdl file to extract that configuration.) It could not show positioning and orientation errors since it doesn't "know" to what the reference point relates. And, without analysing the Flightsim mesh, such a feature could not highlight elevation, i.e., Z, errors. So, how much use would it really be?
When I'm developing arrays, I have FSX running. I compile the array and library to my Scenery Library and with three clicks (World, Scenery Library, OK) my array magically appears along with all the associated features. (Of course, this convenience is not available with FS9).
Don