[Username]

Well I'm no programmer but I've been messing around with a little program called Reverse Engineering Compiler (REC) http://www.backerstreet.com/rec/rec.htm You just download and install it to a folder, trigger the exe and point the GUI to DGen.exe using the File>New Project Menu. It takes about a minute to analyse DGen and then shows what it contains. Lots of code strings... and other things. I've only once used a hex editor so don't know much about the process but it may be that Dgen could be simply updated to include extra maps and aircraft by that means.

Trouble is, you need to drill down through the areas and regions of code (using the decompile command on the interface) to determine the function of each - or so it says on the tin (!)
I don't have the knowledge to do that, but this may inspire someone else to have a crack at it.