Bump because this is really frustrating. I had it working perfectly, I could save the tile array data file and it would be chock full of json data, but now it only gives me blank cells. Also, my problem with the release version not even downloading the file (instead, it just opens a blank tab in your browser) still remains. My code for this system is above, please help!
Here is the version uploaded to newgrounds. Click the save button to replicate the tab issue.