Very impressive stuff, but looking at the models raises a question in my mind. Why do the parts look like they have about an inch of supporting, sprue-like structure beneath them? Wouldn't it be better to have them be closer to the surface so as little material is wasted in the supports as possible?
sometimes these structures act as heat sinks to ensure even heat dissipation throughout the part and improve conformity
This is a photopolymer printer - while the reaction is mildly exothermic, the amount of heat produced is negligible.
The supports are necessary, as they are in most 3D printers that aren't using a powder substrate, to hold the part as it's printing in air. The specific distance from the build platform is determined in software, and is a consequence of a variety of factors, having to do with optimizing resin flow around the part, to ensuring adequate adhesion to the build platform.