Wow, well done!
These days I don't have time to "play" with construct but I took a quick look at your project.
I'm interested to see how you solved the problem of updating a tile from js.
It is interesting to see that in my last project (which will end when my honeymoon returns) I followed a similar but different approach.
You call a function (C3) from js with parameters X and Y
I instead calculate the value of the single tile to be modified and use it as an argument for a C3 function.
The result is the same, I think. I wonder though if yours is more efficient.
However, it would be useful to edit a tilemap directly from js.