Just took a look at the movie, the output seems to be coming out of ZBrush as a .mpg / mpeg-1 format. I don’t know of a way to change that in Zbrush itself. We don’t have support enabled for mpeg-1. (if you check in terminal “rv -formats” you can see a list of support codecs and containers.) I’ll check into why, as it should be unencumbered. (Given the age of the format, I don’t see this requested, so I’m not current on what if anything kept us from including this.)
A workaround would of course be to convert it to something like mp4/h.264. This loads up just fine on conversion. Thanks for dropping us a note about this!