I think your file has become corrupt somehow. I just installed .91 and it worked well. I hadn't installed and ran this track in quite awhile, and it's good to run it again.
Sorry guys but I don't understand. Why are you trying to use that VERY old version while we released the definitive and complete TigerMoth, which is the SAME track??
Of course I'm not supporting this project/thread anymore as it is technically done in the form of ISI TigerMoth.