(Please note, these video files are very large and will take time to buffer, view, and download)
Step 1. Press the play button, then immediately press the pause button.
Step 2. Leave the video alone for 5-10 minutes. (Do not close the web page)
Step 3. Come back to the video and press play again.
This should have allowed the video to buffer and should play faster.
If it still stops during playback, leave it on pause for longer, up to 10-20 minutes, and it should fix it for you.