That's similar to a lot of engines that have gone before it, especially large diesel engines. I think it is very close to the Challenger tank engine.
Also has elements of the Australian 6 stroke engine that had its valve timing controlled by an opposed piston moving at half speed opening ports.
http://www.jack-brabham-engines.com/product.aspx?tech=1&ID=2But it brings everything together in a unique way. The most unique is the power of the top piston is harnessed to the crank by that long con rod. I think this could be a weakness or a limit to revs. In general the difference in length and weight, as well as the angle of the dangle effect on torque of this con rod will bring at least limitations. The large separation of the inlet and exhaust ports might bring up some interesting and unfamiliar gas dynamics.
They make some big and vague claims as to improved efficiencies, 40%, but don't explain where the efficiency is coming from and its not obvious to me. Whereas I can see and understand the mechanical efficiency of this Aussie invention.
http://www.revetec.com/gallery_render_031.htm (They don't say it but I think they are having problems with the bearings, wear, on the cam face. I believe that that is the 'hold up' in reaching production.)