Me too - one video sequence gets to 18%, another to 90% consistently before it freezes and I need to restart. It does produce a partial output file, but only partial. I've tried deleting clips at the lime position of the lock-up but continues to hang. have also removed all the audio to try to reduce complexity, but no results....I'm using a very very new computer, bought yesterday, so latest CPU, memory and drivers - do don't think that's it... HELP - any suggestions?