I guess you are saying gpl only crashes with this track?
It's not unusual for an add-on to cause a CTD but if gpl crashes as you
try to exit that suggests you may have some read-only or corrupt ini
file (possibly the track.ini for Brands) since gpl updates your best
laps etc when you exit.
Try deleting the track (delete the folder, then remove it's entry from
your season.ini etc & correct the number of tracks) and re-install. Have
a look to see if there is a patch for that track, and search RSC to see
if anyone else has had the same problem.
If all else fails try applying the voodoo fix (most tracks offer one).
It'll reduce the texture size so it won't look as pretty but it's
usually a guaranteed fix-all for add-on tracks.
Malc.