I can say most definately, if it crashes when you hit "M" for map, you have a corrupted file in Part 1, I know because I have suffered that several times, and the only fix I found is to reinstall that particular Part 1 again.
I have had this happen on my own PC when I have been checking the airfields, why I do not know, but that is how you fix it. That means you should always save your original Part 1 zips just in case (after you have proved that they are okay to start with) you have this problem in the future.