Preset made:

Result from opening the same file:

JSON file created:
https://pastebin.com/xyucVsAQ

When trying to test around #1, Minecrak told me you need to Save As even with 0.0.3, whereas I was using Save.

But in my testing, both 0.0.3 and 0.0.5 save and open fine.

I'm guessing the above error is caused by my crazy high coordinate edges?