Thanks for sending your files over. I have tried them on two of our test computers. They work on both without failing the export.
It’s funny though! When I play the resulting mp4 videos they look perfectly fine – however, when I scrub the videos (using the native Quicktime player on Mac) I get glitches similar to the ones you got. And when I play again – the glitches are gone.
I’m curious, do you get the same? I mean, when playing the mp4’s they look fine, but the glitches happen when scrubbing?