Well, I can't read the site (the page seems to be gone) and it's in Chinese (I think)...
But the transformation seems pretty straight forward. It looks like the parts came from a cheap point & shoot magazine subscription camera.
The switch simply gets soldered to the hotshoe contacts.
If it were my camera, I would have put the flash on top as to imitate the look of the original as closely as possible.
It looks like he took out all the mechanical parts that make the magicube trigger. These flashbulbs didn't need electricity to work. They had a pin that was struck just like in a gun. Pyrotechnics at their best.
The trick is in positioning the switch at the right place. You have to open the shutter manually and position the switch so that it fires when the aperture is fully open. A simpler hack would be to simply put a 1/16 case jack in the camera with the switch. The best would be to make a special body addition that contains a complete flash unit... Tons of possibilities.