Comment Jumo (Score 1) 570
I thought it looked like a variant on Jumo/Culverin, therefore will have the same problems of what happens if one cylinder starts to fire ahead/behind of where it should. This pre-ignition or non-ignition problem was solved in the Deltic. Oddly enough the Deltic engineers never realised this until they fired the first prototype up and found the problem had miraculously disappeared (because they'd accidentally designed it away).
Thinking on that, when I look at the animation on their website, I wonder where does the gas at the back of the outer cylinders go?