Are you sure you didn't set low-detail with the viewport cranked way down? I played it on the same model ~~with a math co-processor~~ and it could not handle high-detail and the large viewport in the video.
Edit: I'm fairly certain I had a math co-processor, but I'll defer to you on this detail just in case. That would certainly make a sizeable difference.
Why Threema?
The largest criticism levied against Threema: