I have an airline PC game that is 12+ years old that I really enjoy playing, but would like to be able to update it to more modern types of aircraft, etc. that were not around when the game came out. The files are .adf. I have tried downloading a few different programs (Adf opus was one of them), but cannot get anything to work, not sure why (Generally they will give an error when trying to open the file). I am pretty computer literate, but not very much so in this area. If anyone could help me out or point me in the right direction, I would greatly appreciate it. Thanks!