Hi All, I know this has probably been discussed a million times but my search brought nothing back. Tonight I was flying and was told to proceed direct to a certain leg - normally when i click this my sim drops to less than 1FPS until I hit Execute.  Tonight though, when I did this DIR TO i also got an altitude error. Something I could not correct in flight. Basically I was stuck in this 1FPS stutter because I could not Execute the change. I had to close the sim and wasting a lot of