FWIW let me post my "frozen" experience here so you may hopefully find a way to get rid of it.   Basically it happened 3 times when I tried to select ARR rwy for ARR airport when no departure airport was selected. I have 3 instances where that happend:   1. Silly me wanted to fly the 500 from Saba to TNCM. Since Saba is not in the FMS database I just selected TNCM as arrival and when I clicked on RWY10 for ARR rwy the system came to a hold. Luckily I was still at the ramp...