I think the javascript code has been minified or something, which makes it look complicated.
I'm not into code that much (which is why I love Construct 2 so much after all ^^ ). Yes I think it's just flat blocks but pushing the arrows buttons creates events that resize the blocks. If you look very closely at blocks with ladders on top of them you'd expect real 3D to display the sides of those blocks while they are just 2D sprites which change sizes. As I said this is very well done and seems complex but by trying to reproduce the concept in a more simple way with fewer blocks for a start I'm sure it can be done. After that it's just adding more variables and elements but sticking to the same logic.I'd say something like:
A full row of blocks contains 10 blocks in line with each a letter assigned: A B C D E F G H I J
if rotated left: then A size= -30 B size = -20 etc.. etc.. Just throwing ideas here.