I have just browsed through the blog of the project manager at http://tagebuch.miniatur-wunderland.de (it's in German). Until now the only thing I could find regarding the programming are the following numbers[1]:

The control software has 145.000 lines of code[I guess for the whole model, not just the airport]

Just the airport control software has 70,000 lines of code.

He has added 200,000 numbers just for the configuration.

[1] http://tagebuch.miniatur-wunderland.de/eintrag/aus-dem-leben... (German)

http://translate.google.com/translate?hl=de&sl=de&tl... (English with Google translate)